Jobqueue randomly not processing

[talkingnews]

ISPconfig 3.0.3.2 on Ubuntu 10.10 64 on a vps.

Spent the weekend on a wild goose chase trying to track why changes made in the control panel weren't working.

Finally found today that some jobs happen after a minute, some take 5, 10, 20 minutes.

So, I manually ran

/usr/local/ispconfig/server/server.sh

Nothing.

Dug around inside and ran

/usr/bin/php -q /usr/local/ispconfig/server/server.php

and it updated the job queue. Made another change to test.
This time /usr/local/ispconfig/server/server.sh worked.

Next 10 times, both files, despite 2 jobs in the queue, nothing worked. 11th time, it worked.

This is all getting a bit confusing. I've seen mention of turning on debugging in /usr/local/ispconfig/server/lib/config.inc.php but I don't actually see what line that is.

Thank you.