K+H UE100 question

[mik]

Gentelmem, I'm service a pair of this EQ,  I have done a total recap, but wen I act in the filter ( baustein )  C and D adding DB they still pop loud, in boost position in Mid high section some short whistle accur... 

how to fix  ?

thank you

 

[abbey road d enfer]

It's very difficult to troubleshoot at distance, but I would suggest you check capacitors CC10 and CD10; they are not on the boards, they are directly on the switch banks.
When there are loud clicks, it generally means there is a DC voltage difference that shouldn't be, but it could also be a switching issue, with the circuit oscilating during the brief time when the contacts are not engaged..

 

[mik]

Thank you, the 2 capacitors off board was changed at first. All capacitors are new
Maby dirty switch??