I recently re-opened a project I saved about a month before. Never had a drop-out problem before with my Cakewalk UA-25EX which I've had for over a year (maybe 2).

Anyway this project would show "DROP OUT" in the transport window after less than a second of trying to play.

At first I thought my UA-25EX must be having a problem. But no. Other applications worked fine through it.

Then I tried loading a different Sonar X1 Expanded project. Played just fine. Same audio settings.

Next I loaded my buggy project and the working project into the same Sonar X1 application. I could switch between them by selecting different Windows.

Eventually I got my buggy "dropping out" project by deleting the track folders containing Dimension Pro soft-synths. No more drop outs. Undo track delete. Drop outs.

Tried loading a new patch into the dimension pro soft synth. Still drop-outs.

My working project, however, has Dimension Pro soft synths.

Baffled. Completely baffled. I don't want to have to delete my soft synths just to make my project work?

My system: Sonar X1 Expanded 32-bit on Windows 7 64-bit with UA-25EX USB sound card.

Actually it was just deleting ONE of the Dimension Pro soft synths that fixes this. One that has the Syn Bass 03 patch loaded. The song still plays fine with the other Dimension Pro 1 soft synth and DreamStation and SessionDrummer 3 soft synths.

Okay this gets pretty freaky.

If I set my Dimension Pro 1 to the Syn Bass 03 or 04 patches I get drop outs or audio corruption.

If I set my Dimension Pro 1 to any of a bunch of other patches I don't have a problem.

So it's not necessarily necessary to delete the soft synth altogether.

But I don't understand. I was using Syn Bass 03 just fine before!

Try this.

Insert another instance of dim Pro and select the Syn Bass patch
Copy your existing Midi data into the new Midi track
Delete the old instance of Dim Pro