In the Part List, only one instrument can have the 'solo' box checked. Clicking on the box for another instrument causes the first one to be deselected. I would find it useful to be able to have more than one instrument soloed at a time, so that I can easily listen to a few parts at once without having to click 'mute' on the other parts. This feature is common in other programs, and I hope it's not to difficult to program.

Thanks.