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Discussion Starter #1
So after meeting a member here with a setup much better than my previous one I decided to change some things. He is running iPhone to helix via usb through camera adapter with the hec card. After an Apple update he told me as well as others on here have noted they lost the ability to charge while also getting the "this device is not supported" message. I was pretty annoyed but set it up for charging in hopes that it would get a software patch on the Apple side. Got my new set up going which consists of, Apple iPhone7-amazon lightning 3' extension-Apple camera adapter-18' mini usb to HEC in the helix mini. It works and does what it is suppose to. Met with another member that noticed something VERY weird to him which was I had volume control while running "Digital." He was saying the phone thinks I'm plugging headphones in and is out putting an analog signal. After he mentioned this I did think back to when I used my phone into a kenwood headunit it turned the volume control off. So fast forward to today met with a friend for a test we used Apple iPhone 7-Apple a/v adpater(hdmi out as well as charging)-powered hdmi to toslink converter-toslink directly to helix mini. No more volume control. What are yalls thoughts on this?


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Apple products have volume control through digital just like android based players. The AV adapter with HDMI is why you have no volume control with that particular setup.

We are still working with Apple to get them to update and fix the charging issue as well as the "device not supported" message.
 

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Discussion Starter #3
Apple products have volume control through digital just like android based players. The AV adapter with HDMI is why you have no volume control with that particular setup.



We are still working with Apple to get them to update and fix the charging issue as well as the "device not supported" message.


How is it digitally changing the volume? Why is there volume control on the camera adapter and not when running the av to hdmi to toslink?


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My guess is that Apple could but didn’t put volume control on the HDMI AV adapter because in majority of instances they are used with AV receivers or equipment that have their own volume control.

The USB adapter works to output USB audio but I have never seen any Apple literature (I could be wrong) about that being an Official use for the USB adapter.

It’s primary purpose was for external camera use.

The digital audio out functionality is just something us audiophiles found out and use to our advantage.

The iOS device is definitely NOT outputting analog signal through the USB adapter.

Like most things Apple, you won’t get the true details of how, but digital volume control works by truncating bits of the source material.

So... even though one can use the iOS device for digital volume control.. I lean towards leaving the iOS device at 100% volume and letting the DSP with 24-32 bit processing power do the digital volume control to minimize any loss in resolution and dynamic range that comes with digital volume control.

Brax DSP/MX4 Pro combo is the only company/gear I know that properly addresses digital volume control to avoid any resolution/dynamic range loss.
 

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I have no reason to doubt dobslob, but I’ve hooked my iPhone to hundreds of not thousands of units and when connected the volume goes away...

The only thing I’ve ever used plugged into lightning with volume control is headphones (or the analog signal)

Maybe he’s right in saying the aV adaptor does send digital to the hec
But the question is: is it getting fed analog or digital.

Does the AV adaptor have a ADC in it with volume embedded

Just sayin
 

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Discussion Starter #6 (Edited)
I have no reason to doubt dobslob, but I’ve hooked my iPhone to hundreds of not thousands of units and when connected the volume goes away...



The only thing I’ve ever used plugged into lightning with volume control is headphones (or the analog signal)



Maybe he’s right in saying the aV adaptor does send digital to the hec

But the question is: is it getting fed analog or digital.



Does the AV adaptor have a ADC in it with volume embedded



Just sayin


What I'm wondering is with the camera adapter issues it calls for a digital signal get the "this accessory isn't supported" issue and spits out an analog signal where the a/v adapter calls for digital in a different way and it actually gets it? The A/v adapter was charging as well too


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My guess is that Apple could but didn’t put volume control on the HDMI AV adapter because in majority of instances they are used with AV receivers or equipment that have their own volume control.

The USB adapter works to output USB audio but I have never seen any Apple literature (I could be wrong) about that being an Official use for the USB adapter.

It’s primary purpose was for external camera use.

The digital audio out functionality is just something us audiophiles found out and use to our advantage.

The iOS device is definitely NOT outputting analog signal through the USB adapter.

Like most things Apple, you won’t get the true details of how, but digital volume control works by truncating bits of the source material.

So... even though one can use the iOS device for digital volume control.. I lean towards leaving the iOS device at 100% volume and letting the DSP with 24-32 bit processing power do the digital volume control to minimize any loss in resolution and dynamic range that comes with digital volume control.

Brax DSP/MX4 Pro combo is the only company/gear I know that properly addresses digital volume control to avoid any resolution/dynamic range loss.
I don’t believe he is saying it is putting analogue audio out via the usb interface, more that the phone believes it is actually an analogue device (like a headphone for example which is analogue after the lightening plug) and trying to modulate it’s volume

I am also firmly in the camp whereby I have never had a volume control when it’s connected and feeding digital audio to another device, my pioneer double din with car play is definitely no volume control, Bluetooth or aux cable or headphones all have volume control enabled, so no I am fairly sure if there is a volume control it’s not outputting via digital also

sorry Doug but I’m with the guys here... fingers crossed you sort it soon as I’ve never had digital straight into a usb hec as I recently bought the camera kit unaware of this issue ?
 

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The only thing I’ve ever used plugged into lightning with volume control is headphones (or the analog signal)

Maybe he’s right in saying the aV adaptor does send digital to the hec
But the question is: is it getting fed analog or digital.
Lightning headphones and Lightning headphone adapters have DAC’s in them

The Apple USB Camera adapter is a USB host device. There is no DAC or ADC inside of it.

Apple’s Lightning Port is ALL digital. Plain and simple.
I don’t believe he is saying it is putting analogue audio out via the usb interface, more that the phone believes it is actually an analogue device (like a headphone for example which is analogue after the lightening plug) and trying to modulate it’s volume
Gotcha. Yes it is a form of device misidentification. I’m sure Doug can elaborate further why that’s the case specifically for the USB HEC.

However, as Doug previously mentioned, iOS devices are also able to modulate the volume. Lightning is digital and USB is digital which can only mean a form of digital volume control is implemented by the iOS device.

Bluetooth audio is also digital audio. iOS devices let you control that volume as well. So iOS digital volume control is not a foreign notion.

Current methods of digital volume control does mean losing bits as volume is decreased (inaudible in most cases but probably the reason why digital volume control is disabled with many ‘recognized’ or ‘compatible’ connected digital audio devices). The specific dithering method or algorithms Apple is using for digital volume control will probably never be disclosed unless we have an Apple engineer in our midst?

What I'm wondering is with the camera adapter issues it calls for a digital signal get the "this accessory isn't supported" issue and spits out an analog signal where the a/v adapter calls for digital in a different way and it actually gets it? The A/v adapter was charging as well too
Lightning can only spit out digital. I do find it strange how CHEAPER aftermarket Apple Lightning USB Camera adapters on Amazon can still allow for charging with the Helix USB HEC despite still bringing up the error pop up message.

This aftermarket camera adapter is a current workaround. Error may still pop up but the iOS device will still charge. Confirmed for iOS 12.1+ with Helix USB HEC:

https://www.amazon.com/HENKUR-Adapter-Charging-Interface-Compatible/dp/B07GJ9TYWP/ref=mp_s_a_1_3?keywords=henkur+usb+camera+adapter&qid=1559317943&s=gateway&sprefix=henku&sr=8-3

We are still working with Apple to get them to update and fix the charging issue as well as the "device not supported" message.
Maybe Audiotec Fischer can make their own aftermarket Lightning USB adapters? Address the market for an ‘audiophile’ Lightning USB Adapter...
 

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Discussion Starter #9
Lightning headphones and Lightning headphone adapters have DAC’s in them



The Apple USB Camera adapter is a USB host device. There is no DAC or ADC inside of it.



Apple’s Lightning Port is ALL digital. Plain and simple.





Gotcha. Yes it is a form of device misidentification. I’m sure Doug can elaborate further why that’s the case specifically for the USB HEC.



However, as Doug previously mentioned, iOS devices are also able to modulate the volume. Lightning is digital and USB is digital which can only mean a form of digital volume control is implemented by the iOS device.



Bluetooth audio is also digital audio. iOS devices let you control that volume as well. So iOS digital volume control is not a foreign notion.



Current methods of digital volume control does mean losing bits as volume is decreased (inaudible in most cases but probably the reason why digital volume control is disabled with many ‘recognized’ or ‘compatible’ connected digital audio devices). The specific dithering method or algorithms Apple is using for digital volume control will probably never be disclosed unless we have an Apple engineer in our midst?







Lightning can only spit out digital. I do find it strange how CHEAPER aftermarket Apple Lightning USB Camera adapters on Amazon can still allow for charging with the Helix USB HEC despite still bringing up the error pop up message.



This aftermarket camera adapter is a current workaround. Error may still pop up but the iOS device will still charge. Confirmed for iOS 12.1+ with Helix USB HEC:



https://www.amazon.com/HENKUR-Adapter-Charging-Interface-Compatible/dp/B07GJ9TYWP/ref=mp_s_a_1_3?keywords=henkur+usb+camera+adapter&qid=1559317943&s=gateway&sprefix=henku&sr=8-3







Maybe Audiotec Fischer can make their own aftermarket Lightning USB adapters? Address the market for an ‘audiophile’ Lightning USB Adapter...


That is weird the aftermarket adapters will still charge. I'm pretty annoyed with that fact right now due to my longer drives to work after waking up and all jazz I get to work already down to 70-80% battery. So I did some testing with the Apple a/v adapter and an hdmi to optical converter box. It worked flawlessly and charged. So the next thing I'm going to try is Apple a/v adapter to hdmi cord -unpowered hdmi to optical converter into the dsp. I think hdmi will be more durable in a car since I can't use coax.


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Lightning headphones and Lightning headphone adapters have DAC’s in them

The Apple USB Camera adapter is a USB host device. There is no DAC or ADC inside of it.

Apple’s Lightning Port is ALL digital. Plain and simple.


Gotcha. Yes it is a form of device misidentification. I’m sure Doug can elaborate further why that’s the case specifically for the USB HEC.

However, as Doug previously mentioned, iOS devices are also able to modulate the volume. Lightning is digital and USB is digital which can only mean a form of digital volume control is implemented by the iOS device.

Bluetooth audio is also digital audio. iOS devices let you control that volume as well. So iOS digital volume control is not a foreign notion.

Current methods of digital volume control does mean losing bits as volume is decreased (inaudible in most cases but probably the reason why digital volume control is disabled with many ‘recognized’ or ‘compatible’ connected digital audio devices). The specific dithering method or algorithms Apple is using for digital volume control will probably never be disclosed unless we have an Apple engineer in our midst?



Lightning can only spit out digital. I do find it strange how CHEAPER aftermarket Apple Lightning USB Camera adapters on Amazon can still allow for charging with the Helix USB HEC despite still bringing up the error pop up message.

This aftermarket camera adapter is a current workaround. Error may still pop up but the iOS device will still charge. Confirmed for iOS 12.1+ with Helix USB HEC:

https://www.amazon.com/HENKUR-Adapter-Charging-Interface-Compatible/dp/B07GJ9TYWP/ref=mp_s_a_1_3?keywords=henkur+usb+camera+adapter&qid=1559317943&s=gateway&sprefix=henku&sr=8-3



Maybe Audiotec Fischer can make their own aftermarket Lightning USB adapters? Address the market for an ‘audiophile’ Lightning USB Adapter...


You sound like you know what your talking about. I never knew that.
And makes sense why the lightning aux jack is a dongle.
So the device says weather volume is unlocked or is it a different protocol all together? Dosent apple have there own transfer protocol over lightning or is it PCM or m4a codec or something.....whatever it is, does it change SQ at all ?
 

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You sound like you know what your talking about. I never knew that.
And makes sense why the lightning aux jack is a dongle.
So the device says weather volume is unlocked or is it a different protocol all together? Dosent apple have there own transfer protocol over lightning or is it PCM or m4a codec or something.....whatever it is, does it change SQ at all ?
Not sure if its PCM or some proprietary codec either :(

I was very very curios too when the device not supported error first began! Then rummaged the web and other forums for what’s goin on but these are the questions only Apple can answer.

I’m wondering if Doug has more insight and is able to disclose what is not properly communicating with what. Is it Apple’s end? Is it Helix’s end? Both?

Everything was working just fine until Apple decides to push through an iOS update..

But then again I don’t see any reference from Audiotech Fischer that the Helix USB HEC is designed to a specific USB Audio Class standard (1,2,or 3?) maybe causing the iOS or Apple Camera Adapter to not properly recognize the Helix USB HEC?

Here was one of the cool things I came across about the Lighting Headphone adapter:
https://www.ifixit.com/News/apple-audio-adapter-teardown
 

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Using the Apple camera connection kit to give a usb connection and when plugged into a Topping D10 DAC shows the volume control and it’s definitely digital output from the lightening port.


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Discussion Starter #13
Using the Apple camera connection kit to give a usb connection and when plugged into a Topping D10 DAC shows the volume control and it’s definitely digital output from the lightening port.


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Interesting. What are you running out of the D10?


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Just found this thread. It may have been my original thread about the camera kit problem as I posted a while ago.


Ultimately I found that a low cost thing from Amazon worked. Gave an error but also let digital audio out and charged the phone. (latest on ipod touch on ios 12.1 and iphone x on latest ios)


It is digital out as the Onkyo HF music player app plays 24/96 files no problem, and the iphone won't play them natively iirc.


I have volume control on the devices but always set it to max when using them as an audio feed, and use the URC.3 for master control.


The original apple camera kit 3 works fine and charges with no error codes with either the ipod/iphone playing usb out into a USB dac in the home, so I guess it is something in the Helix it doesn't like.
 

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On a somewhat related note....

I have the newest iPad Pro and Apple has ditched the Lightning port on it for a USB-C. The USB-C port allows the iPad to be used with external DACs without the need for any dongle.

The unfortunate part is that the Ipad Pro requires a huge amount of current to charge, and very few DAC devices would offer enough juice for that. So, we still need to use a dongle for charging.


However, I would expect that future iPhone models will begin to go to USB-C and since an iPhone is much smaller than an iPad, the current draw should be more reasonable. I would expect that eventually we will be able to run a USB-C cable to a DAC and have the iPhone charge.
 
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Just found this thread. It may have been my original thread about the camera kit problem as I posted a while ago.


Ultimately I found that a low cost thing from Amazon worked. Gave an error but also let digital audio out and charged the phone. (latest on ipod touch on ios 12.1 and iphone x on latest ios)


It is digital out as the Onkyo HF music player app plays 24/96 files no problem, and the iphone won't play them natively iirc.


I have volume control on the devices but always set it to max when using them as an audio feed, and use the URC.3 for master control.


The original apple camera kit 3 works fine and charges with no error codes with either the ipod/iphone playing usb out into a USB dac in the home, so I guess it is something in the Helix it doesn't like.


Do you have a link?


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