1. To change Record Bit-Depth from 16 to 24-bits. This is a common complaint, or at least stumbling point for folks, and if it is what I think it is, the fix is easy.
The bit-depth is displayed in the transport bar, and in a couple of places in Preferences. The place to actually CHANGE it is in Edit>Preferences>File>Audio Data. Once there, you will see Record Bit Depth, with a drop-down arrow. Expand the list and choose 24-bit, then click Apply.
Please note that this will only affect NEW audio. (It may only work for brand new projects, but it MIGHT work for new clips within existing projects. All of my stuff is is in 24-bit, so I do not know for sure about this aspect).
In any case, the above is where and how you change it.
2. I am going to recommend you try the following settings, to get better latency and have your computer not have to work so hard:
Audio Interface: 24-bit, 44.1 k or 48 k Sample Rate, ASIO Buffer Size of 128
Sonar: Sample Rate 44.1 k or 48 K (MUST match setting on interface), Record Bit-Depth 24-bit. You want to try to shoot for a Sonar-reported Total Roundtrip Latency of at or a little below 10 milliseconds, for recording. (for mixing/mastering, you can jack up the latency for some of the more cpu-intensive plugins or those that use look-ahead processing). You will see the various latency values reported by Sonar at: Edit>Preferences>Audio>Driver Settings.
There are some buffers that you may choose to adjust at some point. The Playback I/O Buffer and Recording I/O Buffer sizes default to something like 250, or 256. Some folks get better results upping those values to something like 512. So, after you try out the other settings I posted above, you may circle back to try adjusting these buffers, as well, to see if it benefits performance on your system.
I hope the above settings give you a good balance between resource demand and audio quality.
Please give them a shot and post back with your results.
I use Sample Rate of 48 K, 24-bit recording, ASIO Buffer Size of 128, and have a Total Roundtrip Latency running at a little over 9 milliseconds, which works fine for me. I have not thus far had to adjust the Recording and Playback I/O Buffers, and am quite happy and quite stable with these settings.
Bob Bone