Doepfer

Hi everybody! I just got a second hand Doepfer system. After a few 
days I realised the Lfos (A145 & 147) interfering with my A110 
oscilators (x2) and filter modules: a121.(I can hear easily that the 
Filter modules get intefered when they are self oscilating). I tried 
to find info everywhere and tested all the tipps I found but nothing 
gets rid of it. It has a +5V xtra power module but I removed it too 
but nothing gets better. I even tried to dismount all the modules and 
just leaving 1xA110 and 1xLfo and moving around them in the rack. 
Even tried to swap the oscilators and Lfos (from a145 to A147) but it 
doesnt get better. I would really apreciate some help if anybody can 
think of something. Greetings Asbjörn