Thanks for the suggestions! I think I'll move the context-sensitive popup menus into the main version -- I assume that's what you mean by right-click menus? The looped play stuff is broken -- I hadn't noticed the problem. I'll also add some mouse-oriented way to play from the cursor. For multichannel files, you can set the 'unite' and 'sync' buttons and all channels will be displayed and acted-upon together -- is that what you have in mind? On the zoomed FFT -- it's been on my TODO list for about a decade. You can drag the frequency (x) axis to zoom in on the lower frequencies, and there's a complicated way to zoom using the spectro* variables. To dump the current spectrum to a text file, you can use the peaks function: (peaks "fft.data") for example. Anyway, I'll get to work on this stuff; GUI here I come (sigh)... Thanks again!