I've run into an issue with projects created a few weeks ago.

If I try to record a new audio track on an old project, it's almost as if there is a 100ms delay on the real-time echo.

If I try to record a new audio track on a brand new project, there is no delay.  

The new project is based on the same template as the old project.

It's only started happening after I installed the  driver for a new mixer, but I can't believe that's the problem as un-installing the new driver doesn't make the problem go away.  And also, the latency doesn't happen with new projects.

Any suggestions?

All I know is Behringers drivers are reported to be terrible. I think people end up using ASIO4 all which also kinda sucks.

This music store I was in the other day said they have had to stop recomending Behringer stuff as it is not worth the complaints they get down the road. He said they don't even design their equipment but copy other brands and then use cheaper components.
I have a little 12 channel mixer and it lasted 5 years and is now a door stop. Sounded good when it worked...If you can try and get your money back and buy the Mackie.

I found out the problem.  It's the LP-64 multiband compressor !

If I remove this plug-in from the master bus, the latency goes away.

Disable/bypass the plug-in doesn't work, it has to be deleted !

Johnny, how did you work out it's a Behringer from his post?

Oh he had just posted another thread and sometimes I pay attention ha ha.. http://forum.cakewalk.com/tm.aspx?m=2675835 I find it very strange to have to remove a plug in?? As far as I understand bypassing removes the plug in from memory and from any use of the CPU, It becomes a tiny bit of code pointing the way back to re-opening the plug in. So not 100% sure you actually found the problem, but, stranger things do happen and what ever get's results is a solution.