Greyed Out Track Selectors Help!

[kately]

Hi,

All of my non-grouped tracks suddenly have greyed-out track selectors and will not produce sound when selected or soloed. If I group them they will play back when the group is soloed ( not simply when the group is enabled, it must be soloed.) Restarting and/or the BTA button does not fix this. All tracks have speakers on, volume up....

Is there a key command I may have accidentally hit which only enables soloed groups? This happened while I was copying and pasting automation envelopes on a track...if that helps solve the mystery?

Thanks a ton!