Has the bug occured in previous versions? If yes, please specify version(s): .54 & .53 (before those it definitely didn't)
Description of the bug: On some of the tabs, especially the instrument tab, some of the sliders and pulldown menus will disappear when jumping between tabs. most notably it's the 'plugin/midi' pulldown menu on the instrument tab.
another thing that has been annoying me for ages is that if you add some randomizations in the instrument tab the sliders will occasionally disappear. this has been the case since .40 until now, though it strangely doesn't seem to occur in 3.02 anymore.
How often does it happen?:
How to reproduce (step by step description):
create a new song, create a new instrument, go to the sample tab, go to the instrument tab again... 'plugin/midi' menu will be gone. doesn't seem to be connected to screen res, tried with both 1024x768 and 1280x1024