If you can not create this error, I think a programmer should check the code. Look for program resources that a click consumes. Which are hitting the roof on several clicks. Why? Because the bug goes away on dsp window close and open... Which should be some kind a window resource initialization - I would guess...
Have you posted your system info? Have you posted a log file including when the problem occurred so that someone qualified can actually look into this for you? (Help=>Logging, System info from main menu just in case)
I cannot reproduce this either on my system - so undoubtedly it is only linked to
your system and/or a specific configuration of JRiver that you and a few others may or may not have done.
I would take a wild guess it has something to do with reordering DSPs, and/or external filters -- but what do I know?!
Maybe a screen shot of your DSP window with any tweaks that the "common joe" wouldn't be using (like convolution and parametric eq.) might help someone get to the bottom of this for you