Last year we replaced the headunit in the HK system, we also installed all the other crap needed for the steering wheel controls. and it all works fine.
untill lately-
We now have interference when on FM, the interference changes with engine revs but is also there with the engine switched off.
no interference with cd's or usb's.
(well respected) installer says its the HK amp,,

any thoughts?
anybody replaced a HK amp?