"Waiting for Adobe Flash Player to connect to debugger..."

Having an issue where after installing 10.1 debug build and then stepping back to 10.0 debug on Windows 7 and Flash Builder 4 the debugger will no longer connect:

http://content.screencast.com/users/IvanSlepchenko/folders/Jing/media/206aa0ea-4c5c-43e6-9 7f2-2f8f58df25ea/2010-05-13_1522.png

After 1-2 minutes it times out with Launch Failed: Failed to connect; session timed out.  Esnure that: 1. You compiled your Flash application with debugging on.  2. You are running the debugger version of Flash Player.

Any thoughts on what may be happening here?  Nothing else has changed and after searching for quite a while for answers nothing has resolved the issue.