LAOS Laser

I've had this problem ever since i put together my laser.

I don't know what's at fault here besides not the power supply, since that has been replaced and continues to show same problem.

When firing for alignment or running a job, the laser will light up as per usual, sometimes it will work normally for a while, other times even after longer periods of cooldown, it will then only partially saturate the metal ring at the beam exit, it will move around and fire the beam off course in a direction opposite the saturated area of the anode with a limited potential.

My guesses falls on the usual suspects in suspected order:

1. poor grounding
2. bad tube
3. poor cooling

I would love to get some input, suggestions for tests, and misc. feedback from anyone seeing the same problem, before i let loose the havoc beam.

Started same thread over at the buildlog.net fora: http://www.buildlog.net/forum/viewtopic.php?f=14&t=2693&p=23311#p23311

Thanks in advance