The Dreaded "Audio Disk May Be Full" error and USB?

I shouldn't be getting it, but I am.

I redirected the audio folder, and picture cache folder to a 1T (empty) SSD ... connected via USB (2.0). All projects have the audio stored in the project file, and are also located in a separate folder on the SSD.

I bought a new Soundcraft UI24r. It also connects through USB via hub (2.0).

I'm forced to use hubs, as my high powered laptop (i7 quad and 8G ram) has only 2 USB 3.0 inputs ... and I've multiple devices needing to connect. 

Everything is reading right in Sonar ... I can see the signal come through the Soundcraft device fine. The trouble is when I roll the tape ... even on a single track. It rolls, but two - three seconds in? Up pops the error.

Does that error pop if there's bottlenecking occurring in the USB? Should that have any impact? Any other ideas why I might be seeing a problem when I roll the tape? Any suggestions that might help?

I've seen suggestion about deleting the picture cache and the audio.ini file ... but Sonar is pointing at literally empty folders.

I'm stumped. Any assistance is warmly appreciated.
 
 

Thanks Jon!

Both hubs are powered, but one is a 2.0 and one is a 3.0 hub. What I'm going to try and do is swap some low demand inputs from the keyboards into the 2.0 unit and free up space for the higher demand SSD and UI24r into the 3.0 hub.

I changed the folder settings in Sonar to point to the empty SSD in brand new (current empty) folder entitled (creatively) R://Cakewalk Projects/Audio and R;//Cakewalk Projects/Picture Cache. I've got Projects themselves being saved under R://Cakewalk Projects/Project Files.
 
So when Sonar looks at the disk where EVERYTHING is being saved, it should see brand spanking new, empty folders. It shouldn't matter to delete the picture cache or the aud.ini file. There's nothing in the picture cache, and the .ini file is pointing the audio to an empty folder for storage.

I did not up the cache size though ... which I will do.

I did see that high CPU usage might be an issue, and I was running a live rig w/ Cantibile 3.0 running and powering several plug ins. I don't know if that's an issue or not because I didn't have time to experiment with things during last night's rehearsal ... which I'd hoped to record w/ the new Soundcraft piece using Sonar.

I was so hopeful. I get the whole band miked up, routed through the mixer and registering in Sonar ... press the record button ... and ............ fail.

I'll work on it in a bit ... but I was terribly disappointed when the error popped and I couldn't record.