Quote:

Even stranger is that all the audio effects function just fine when used « destructively » from the Edit/Audio effects menu.




Two entirely different pieces of code. The destructive effects under the File menu are NOT DX effects at all.

Quote:

I don’t think I made any change to my setup. The only possible factor that may be at work, although this appears a long shot, is that I upgraded my PC Protection package to BitDefender Internet Security 2009.




Try rolling the OS back to the last Restore Point before the update to see. This is reversible if it proves not to be the culprit.

Check your microsoft Directx by typing "dxdiag.exe" without the quotes in the Start -> Run box and hitting Enter. Note the DX version reported as well as performing all the tests.

You may have no resort other than reinstalling PT overtop itself, DX effects and all. You shouldn't lose any of your songfiles at all when doing that. I never have.


--Mac