Hi,
I finally found few minutes to change Q328 and Q330. I used a 2SB649 and a 2SD600. I also reconnected the new Q332 and Q334. I measured the voltage on power transistors. It is mu h more balanced on B now. Is it fixed?

 

Work on one channel at a time.

Install the power transistors. Measure output DC voltage. If the voltage is zero only then connect the loudspeaker. Input a music source and play at low volume levels. If all is well do the same with the other channel.

The show is not over till the fat lady sings, in other words, when there is music to your ears.

 

Work on one channel at a time.

Install the power transistors. Measure output DC voltage. If the voltage is zero only then connect the loudspeaker. Input a music source and play at low volume levels. If all is well do the same with the other channel.

The show is not over till the fat lady sings, in other words, when there is music to your ears.

I have sound on both channels . Thank you so much for your help!!
I noticed that without music source, I get some buzing when incresing the volume above 3/10. I'm not sure that it's related though, it might have been there already before. It's not really a concern cause at 3/10 the sound is already pretty loud.

 

The buzzing is not related. It is likely coming from the power supply.
If you cannot hear it with normal music source I wouldn't worry about it.

Glad to hear you got it working.