Focus FX-1200D problem

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Hi everyone!

I have this Focua Acoustics FX-1200D amp, and I´m having a slight problems with it..the amp came to me with 2 blown ampFET´s and the HIP4080 were dead. -> changed all FETs and that HIP, everything else seemed to be fine, but surprisesurprise NO :D

Amp powers up nicely, but draws excessive current and burns those same two FETs immediately......measured a bit, and there´s a 2,6VDC drive at those FETs they´re at low side. Even if I pull out the HIP, there´s 0,247VDC still.

Now there´s HIP on its place and all other FETs at amp section - amp powers up nicely, green light comes on and output relay clicks BUT there´s a 1,6VDC voltage at output :/

Voltages at HIP:

without IC installed
1: 11.82
2: 12.10
3: 0,000
4: 0,000
5: 0,002
6: 6,27
7: 6,70
8: 0,00
9: 0,00
10: 12,00
11: 0,000
12: 6,52
13: 0,027
14: 0,002
15: 12,08
16: 12,08
17: 0,002
18: 0,039
19: 6,53
20: 0,001

With IC installed on it´s place:
1: 16,52
2: 12,08
3: 0,000
4: 0,000
5: 2,797
6: 6,27
7: 8,05
8: 5,23
9: 5,23
10: 27,38
11: 18,24
12: 15,91
13: 8,69
14: 12,06
15: 12,06
16: 0,000
17: 0,000
18: 2,695
19: 14,15
20: 14,25
 
The resistors I'm referring to are connected between one output filter inductor and pin 12 for 1/2 of the IC and between the other output filter inductor and pin 19. I've never seen them as high as 10 ohms. There is probably another large 10 ohm resistor parallel with a diode (actually a TVS).

Do you have rail-rail oscillation on the output transistors?
 
Oh...wrong resistors :D Yes found the right ones and they measure 0,9/1,0ohms - checked with precision meter -> 0,84/0,96ohms

I´ll try to check that oscillation...but do you have any idea why only those two FETs do burn and rest of them wont?
 
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