I notice that if you have loop enabled and set the metronome to do a one bar count-in, when it reaches the first beat of the looped section the metronome double triggers. Here's a video as proof.
 
http://www.screencast.com/t/e8uqfSUS
 
I sent in a report.
 
Regards
Martin

I can't reproduce that right offhand. What interface and driver mode? If using WDM with more than one interface, make sure you have the correct interface driver selected as Record Timing Master. Are there any FX on buses that we can't see in the video?

It's just a single track project I'm using Asio drivers for the Fireface 400.

Maybe try renaming your AUD.INI file, and see if the problem persists with the default one that SONAR creates. If not, compare the two files and see what's different. If it does persist... I dunno.
 
BTW, I don't think it has any bearing on this issue, but I was surprised to see you're recording at 16-bit sample depth. You might want to change that to 24 in Preferences > Audio Data.

Update your audio interface drivers and firmware.

brundlefly
Maybe try renaming your AUD.INI file, and see if the problem persists with the default one that SONAR creates. If not, compare the two files and see what's different. If it does persist... I dunno.
 
BTW, I don't think it has any bearing on this issue, but I was surprised to see you're recording at 16-bit sample depth. You might want to change that to 24 in Preferences > Audio Data.

Thanks I'll try renaming the file. I didn't realize Sonar defaults to 16bit so I've changed it to 24bit.

Doktor Avalanche
Update your audio interface drivers and firmware.

All drivers and firmware are the latest.