[Elecraft] on PSK the ALC bar setting is no longer stable -- ideas why?

[jsdroyster at nc.rr.com]

Hello to all!  Our KX3 that Larry uses for PSK has mysteriously developed an unstable ALC bar setting.
If we use the mic gain to set it for 4 bars while transmitting, then on the next transmission, without our having touched any controls, it goes back up to 6 or 7 bars.
Any ideas what could have changed to make this happen?
We must have inadvertently changed something but I don't know what.
THANKS!
Julie KT4JR and Larry K4MWE