You are here

Olimp MPK 005, tape speed regulation

Hello, i have a question and i hope for help. The tape speed regulation of my MPK 005 is defective. I have change the transistor VT2, but this helps not. Is it possible that the IC DA 4 (operational amplifier) is defective? Which other options are possible? The motors are ok. I very much hope, you can help me. 
Best regards