STK to TDA7293 conversion

You got it wrong, pin #4 and resistors located on the +/- input of TDA7293 are all referenced to the signal ground, do not separate only pin # 4 from the signal ground via 10R resistor. So, two resistors and the #4 pin are connected together to the signal ground (trace or pcb area you declare as signal ground), from where it connects to the power ground via a 10R series resistor.
As luck would have it, yesterday I was explaining similar things on the Croatian diy forum so I have a ready schematic, slightly modified with 10R resistance for your case.
 

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maxmix69 I did everything you said and the amp exploded 😀:joker:
It worked, the noise was reduced to almost nothing 🙂

Thank you maxmix69 and everyone else who tried to help.

Some pictures:
 

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