I'm getting a delay when I "press" (mouse) Track record button.  Either to turn on the Record or turn it off.
 
If I turn it on or off with my Frontier Tranzport I do not get the delay. 
 
I haven't noticed it in anything else, and the mouse works "instantaneously" with other functions. 
 
I did a forum search and didn't come up with anything before I made this post.

Are you talking about clicking the record button in the transport area, or arming tracks? There are several posts here about a delay when arming tracks. It seems specific to those using RME interfaces. Try searching for the terms - arm, lag, record.

Its when arming tracks.  I'm using a Roland Octa-Capture.  Thus it would appear to affect more than RME.
This is in Windows 7 64 bit OS. 
 

This is likely to be related to your audio interface's driver.  Are you using the latest version?  If so, did you recently upgrade your audio drive and that's when the issue started appearing? 
 
I have an RME UFX and have had this issue for a while, although it was somewhat mitigated by a subsequent RME driver update - the delay is tolerable now, so not a big deal for me.  When I first encountered the issue - both RME and Cakewalk agreed it was an RME issue, hence my pointing you to your audio interface's driver.
 
Russ
 

I also have this issue with the OctaCapture. As soon as I load the mixer interface the record arm button in the track view takes a few seconds to go on or off. I've also found this lag with the input echo button.
If I use a different interface (e.g. my UA-25EX) this behaviour doesn't occur. I can only conclude that there is some issue with the drivers for the OctaCapture. I'm using the latest drivers from the Roland website but this issue has been occurring since I started using the OctaCapture
It's a right PITA when I'm trying to arm more than 1 or 2 tracks for recording.
 
Interestingly, if I shut down the driver interface and use the buttons on the OctaCapture to make selections the lag issue disappears.

I have the latest Roland Octa-Capture driver.   I checked out my Windows 8.1 installation (its dual-boot with the Win 7 so I'm using the same hardware) and its happening in Win 8.1 but not as slow.
 
I will be doing some tracking today and will test further.

More testing.  The delay does not happen with my MAudio Fastrack Ultra 8R.  It does not happen with the Octa-Capture if the Octa-Capture Control Panel is not used.  With the Octa-Capture Control Panel, there is the slight delay.
 
I've marked this as Solved since it apparently is not a Sonar issue.