bitflipper
I never use instrument tracks. They were added in response to a few very vocal users who moaned that SONAR didn't work like Fruity Loops. Wah, wah. I thought they were useless then and I still do. They are, after all, merely an illusion to make two separate tracks appear to be one. They hide important controls and limit your routing options. Their only benefit is to save screen space in track and console views.
IMO MIDI and audio tracks should be separate, because they are very different things. When I am working on a project, I am either focused on MIDI data or audio data, rarely both at once. Instrument tracks force a 1:1 relationship between a MIDI track and one synthesizer, but I often have multiple MIDI tracks feeding a single virtual instrument, or one MIDI track feeding multiple instruments. That is the main benefit of using separate tracks.
Beeps, the above are my feelings as well. Also, I have NEVER had issues with an independent midi and audio track supporting synths. Meaning, they have always worked perfectly for me in this manner. One day, I decided to try the instrument track because I was told "get with the times dude, it's way better to do it this way". Well, it looked cooler and it was nice to do everything from one track, but I had noticed this weird artifact.
My piano would not trigger right unless I reloaded the sound sample. It played like my ASIO buffers were set to 32 or something. All choppy and messed up. Closing and re-opening didn't fix it. I was going nuts. At the time, I didn't know the samples had to be reloaded. Once I did that, the noise went away and stayed away for the remainder of my work in the project.
Close and re-open, artifacts were back. I posted a message on here begging for help because I was really going nuts and wondering how and why this was happening. I've been a Sonar user since the floppy disk days and have never experienced anything like this before. Ed (Bapu) comes on here and instantly remedies the problem telling me that instrument tracks have done the same thing to him numerous times.
I reloaded the track the old way, and to this day, have never had a problem again. I've tried the instrument track things a few more times...same issue, though at random. Sometimes there are no problems, other times these weird artifacts creep in. I can't even write up a bug report for it because I have no idea what causes it other than....if I stay away from instrument tracks, I NEVER EVER get these artifacts. Hope some of this helps bro. :)
-Danny