Am-1780 squeal

[dgrev]

I bought an NOS unit off ebay.

Plugged it in and there is a squeal on the audio regardless of what
socket I plug the C-2298 boxs into.

Suggestions please as to the cause?

Hopefully I can just do a module swap from a dead 1780.

Thanks Doug

 

[papakb]

Change the A80 mic amp module.

 

[dgrev]

Ok, thanks, what I needed to know.