[arm-allstar] Noise from link key up

[Robert Conklin]

Dear Folks, I have a CDM based UHF machine that's been running beautifully
for years now. Have replaced/re-imaged the uSD a few times over that period
as a preventative maintenance measure.
All of a sudden and with no configuration changes it has began making
terrible feedback loop/white noise when key up from a link and it has a
hard time dropping the PTT once keyed.
This does not happen when it's keyed from local RF or keyed from internally
generated telemetry.

Antenna system measures fine.
Cavities measure fine.

Even though it seems to only happen when key up from a linked connection I
tried isolating the cdm exciter from the micor PA with a dummy load, made
no improvement. Turned off the RX radio and it still makes the terrible
noise when keyed up from a connected link.
Possible clue: When linked to different allstar rptr that has parrot turned
on, when I talk thru my repeater the echo is returned from the linked
machine with no noise. Odd.
Any ideas I can chase will be appreciated, thanks!

--
Robert Conklin
*N4WGY <http://qrz.com/db/N4WGY>*