Hi,
I'd try this as a quickshot:
find /etc /root /home -type f -exec grep -l PS3 {} \;
than I'd take a closer look at the files that will show up. And I'd
read bash(1) closely to learn which files are being read in which
order and especially when.
If all of the above doesn't lead me anywhere, I'd start poking
around on a mailing list to see if somebody could explain me what's
going on, but maybe that's just me.
Frank.