100D unstable frequency

[dmalcolm]

I use my 100D with WSJT-X. The wideband frequency display provided with WSJT-X shows what I interpret as frequency instability. It has the appearance of a low frequency sine wave (perhaps one or 2 hz) were changing the displayed frequency traces, which look like a signal waterfall. straight lines are normal. If anyone thinks they may have an answer, I can provide a screen capture. Too make matters more confusing, the problem is intermittent.

[w-u-2-o]

Please post a screen shot.

[w9mdb]

In the Audio tab under VAC1 Monitor do you have "Force" unchecked?
Try checking it.
I found the frequency to be unstable without checking Force

[dmalcolm]

I just tried checking "force" and it certainly is looking better. Thanks.