How are you submitting your jobs? The Qube dialog inside the Maya application? or through Qube GUI? Also, we need more information to actually see why the problem occurs. Can you send us your job log? You can send it to support@pipelinefx.com, the instructions to do so are as followed:
In order to address your problem more completely, please send us the job log directory for the job in question.
You can locate the directory by logging into your Supervisor, and looking for the job log folder in the following location (depending upon your Supervisor platform):
Windows
\Program Files\pfx\qube\logs\job
Linux, OS X
/var/spool/qube/job
In that folder, you will find a numbered directory that corresponds to the number of thousands in the job ID. (ID < 1000 = 0) Search in one of these folders for the one that corresponds to the correct job ID.
Zip up the entire job ID folder and reply to this email message with the zipped file.
If the zipped job ID folder turns out to be larger than 2MB, don't send it, but let us know and we will help you address the problem in an alternative fashion.