Worked here on both .wav and .mp3.
You said you double-clicked? That calls up the Trim Monitor. You need to right click on the edit point.
You need to select the edit point first with the roll edit, then rightclick.
Hold shift for multiple healing.
Sorry I meant to say right click.
Thank you Ann, selecting with the roll edit works. For video tracks I can use either the Selection tool or the roll edit tool but for audio tracks only the roll edit tool works.
You need to select the edit point first
I actually didn't. I hovered the mouse over the edit point and right clicked, one operation, and got the desired menu commands.