MAc wrote:

additional info:

on ssb i hear my distorted voice in headphones when transmitting
(monitor is off)

This gets me thinking about grounding, how good, how old, how far, etc.
is yours? I had similar problems feeding a long wire on 15m and up when
grounded with a 2" wide copper strap to a 10' driven ground rod. Once I
shortened the strap all the problems went away.

Good luck!
- Galen, W8LNA