Same thing happens just resizing the window-- and there are visual glitches (top right corner transparency turns black, the o-scope/info insets flash...)
Those are just minor things, way overshadowed by the addition of channel toggle.
But the pause ought to be fixable by sticking the emulation and audio feeder onto a separate thread (ThreadViewer tells me h6280_execute etc is happening in the main thread.)
And, you really don't need to draw anything if the window is hidden/minimized
(40% time in window_draw...)