Ok guys my problem was in the speaker, to be more precise in two connection on the speaker that are human hair thickness :P. In shop they just solder it to another points, and now it's working very good.

I checked all circuit with multimeter, the is no break in the connection, all cables and boards are good. I think it something with elektronics on main board. I will give headphones to the repair. After i will post whats wrong with them.   Best regards.

Hello guys, i have strange problem. I have Sennheiser PC 350.   they working good but after some time(random) the right speaker stop playing. I manage to find that, when they playing music and right speaker silent, i can short wires with multimeter and speaker playing again.    this is the...