Class-d autostudio

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Hi.

I have autostudio amp, but i don't remember what model it is.
It look same than bxi2006d, but output have 2 relay and something different on output components. 16 irf640 output mosfet.

Amp goes protection mode when start amp. I think power work, because output relay clicks, then amp go protect within 1-2sec. When relay click, speaker terminal have about 15-30v ac, i dont know how much, because im not have good measure meter.
If i remove audio driver board, amp stay power on, but speaker terminal have 14.5-15v ac.
Amp not have output fets this time, when i measure.

Can anyone say what is problem?

card is this, but brown color and center top in card, my card have 2 resistor, and blue have 3(4702, 2002 and 1003).

371044d1379120465-brutus-bxi2006-bxi2006daudiodriverboard01bx.jpg
 
I removed all transistor on this board and all resistor. one transistor hfe is low, but i replaced it. one 4700 marked resistor is burned and i replaced it. But amp go protect without output transistors. and without audio card speaker terminal have about 15v ac, or 7-8v dc and not goes protection.
 
8 mosfet burn if it soldered on board or only few, but marked fets it is parallel.
I need replace one 511 marked resistor on audiocard and i solder two 270ohm reistor in series.

Sorry my bad english.
 

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If multimeter gnd is transformer primary and +/ohm is secondary it seems load some capacitor but ohm stopped 1.57kohm. If meter gnd is transformer secondary and + is primary, my multimeter display flicking, 1 second on 1 second off, but reistance increase but i don't know how high. because i cant get reading if meter is 2mohm or 200kohm, only if i read first 2k and swap to 20k i can get about 8kohm, then meter not show anything.
needs remove transformer for read resistance?
I measure when transformer is soldered board.
 
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