my ic756 has an anomoly impressed on the transmit audio in SSB and AM.

Sounds similar to a pl tone, but much louder. Has about a 100 hz cycle rate(guess).

It is louder when you turn up mic audio and compressor.

It shows up on the transmit scope, too.

Has anyone heard this and do you have any ideas on where to look?

It is not power supply related, btw.

Thanks.

k8vf AT yahoo.com