Hey all,
 
I've become bogged down with a situation that has me rather baffled; If I use an external drive, I can record, playback, process, and so on, to my heart's content without any issues whatsoever. But, if I use an internal drive, everything goes to pot, and I'm lucky to last more than a few seconds before I hit a dropout. More often than not, this is followed by a hung Sonar, and the system taken an age to get back to a useable state.
 
I've tried different computers, with the same result. USB fine, but use an internal SATA drive - HDD or SSD, it makes no difference - and the problem starts. Given the speed difference between USB2.0 and SATA-III, I could possibly understand encountering the issue in reverse, and with everything up to date, on the same system...
 
Any ideas? DPC/Latency is very low, program/background services makes no difference. I've not messed with AUD.ini, or enabled caching, as doing so isn't necessary with the slower option :-S

You may have already done this, but double check Options>Global>Folders.
Make sure you don't have paths leading to a non-existent drive. 
I can't think of much else that would cause this to happen.

I did look at the Folders, although I wasn't looking out for non-existent drives at the time, so I will check on that. Off the top of my head, I don't recall anything there that was wrong.

I wonder if you've hit on the general area that might be causing the issue though, as the system(s) are otherwise running flawlessly.

Nothing wrong with the folders, having now checked, and did a test recording. Interesting, in that recording appears to be fine, but playback won't go for more than a couple of seconds before dropping out.

Potentially resolved.
 
I lowered the playback buffer in Sonar to 64 and no dropouts. It had defaulted to 256, which I'm guessing worked fine for external drives via USB2.0, but was too big when switching to an internal one (in this case, an SSD). It feels like a rookie mistake now, but the internal versus USB thing really had me looking in the wrong direction!
 
I tried the same on a second machine, and same result. This one uses the same make/model of SSD for the o/s, but has two 10Krpm WD Raptors for audio; One Raptor is plugged into an SATA-III socket, the other an SATA-II socket, and as a possible point of interest, the one in the SATA-III socket was fine with the playback buffer lowered from 256 to 128, but the SATA-II one had to go down to 64.
 
I've not been able to do any recording with other channels playing back, but once I have, I'll post to say all's good/bad :)

I saw this post yesterday and it made me scratch my head as well. Having buffers set too high can cause dropouts as badly as having them too low, and I assume that both ASIO buffers and I/O buffers are set higher if running an external drive. These are "system specific" settings and when shifting from an external USB drive to an internal SATA III your "system" has changed quite a bit. You may find you will have to adjust these each time you connect/disconnect that external drive.
 
Generally speaking, ASIO ~128 and I/O (Advanced Mode: Preferences->Audio->Synch and Caching) settings of ~256-512 tend to "work" for systems (with internal drives). Be sure to tailor all three values when you streamline the system. You may find you have to remember the settings for both configurations to be able to "swap modes" seamlessly.

It certainly does appear to be a fair amount of swing between the two, and like you say, all particular to system environment. I've fitted an SATA caddy in the rig that only had USB to hand originally, so hopefully things can stay pretty much the same now until anything under the bonnet gets changed. Famous last words, obviously, lol.
 
Overdubbing with buffers left at 64/256 appears to be ok, though a lot more testing to be done before I'll rest easy :-P