robert_e_bone
I took a quick look in the manual for the Lynx Aurora, and saw a note in there about having to put it into standby mode after settings changes, to save the changes, prior to power being removed.
 
I am wondering if after you make that buffer size change, if putting the audio interface into standby mode and saving its state (and then restarting Sonar), would maybe resolve its jumping back to the 512 settings.  Is that remotely possible?  It seems easy enough to try it.

 
The thing is, I like to use the minimum amount of latency req'd for a project, which is typically 256. I had to use 512 on a project where a couple of plugins (waves vocal rider and soundtoys little microshift, specifically) combined with automation were too much for the 256 setting, and melodyne requires 1024. So it would be nice if Sonar could save the settings specific to each individual project.
 

OR, do I need more coffee? :)

 
I'm putting on a fresh pot ;)
 

I will continue to read and learn about working with settings for the interface, to see if maybe I can figure out something.
 
Bob Bone
 

I appreciate your efforts, Bob.

The ASIO Panel button launches the control software bundled with the audio interface. As mentioned above SONAR has no control over buffer size when running in ASIO mode.
 
The Buffers in Playback Queue and Buffer Size slider are NOT used when running in ASIO mode. This is why the controls are not available.

Thanks for explaining why the controls aren't available, Scook.
There is no way to set the latency from the Aurora 16 or the AES16e card other than a single global setting, set it and forget it. I need to go through Sonar to change the buffer sizes for each project.
 

 
 
 

jonnewyork - it seems to me that running with a buffer size of 256 when recording would drive me nuts with noticeable lag.  
 
I use an ASIO Buffer Size of 128 when recording, and then change it to either 1024 or 2048 when mixing.  The smaller size when recording gives me a Total Round Trip Latency in Sonar of just under 10 milliseconds.  When mixing, the much larger buffer size gives the more robust plugins room enough to do what they need to - such as Perfect Space or LP-64, etc.
 
Generally, for the rest of time, I expect to switch back and forth between a small buffer for recording, and a giant buffer when mixing.
 
Bob Bone
 

That's a great tip for recording.
 
It would be nice if Sonar would remember the buffer size for each project since I do a lot more mixing than recording, though. Somehow it always defaults to 256 when I open a project.