reason for blown amp?( technical Q)

i had everything installed 3 days back. everything was fine. yesterday the amp stopped working. after opening it up , i found on one trasistor was loose because of which MAYB the amp blew. i fixed the Transistor and replaced the Card which had some blown up resistors. ( shown in the pic).

everyhting worked fine for 10 mins. then suddenly i felt as if the bass got less... as if only one sub was working. the amp was tripping as well. after 15 mins , i smelt somthing weird. opened the amp and saw tht one of the capacitors/condenser blew. i replaced the cap in the amp. rewired everything , the amp switches on but trips in high volumes plus the out put is also very less .

any idea y is my amp blowing up again and again? and y is the output so less?
i checked the amp everything seems to be perfect.
mosfet , transistors , chopper , voltage , output , baising , fan , loosening .... everything is perfect.

plus the amp is only running subs at 2 ohms while it is rated [email protected]

card picture by enerlevel - Photobucket