Hello All,I am a first time poster here...We use thermo ICAP 6500 Radial. We recently have been hearing a slight rumble coming from the torch box which seems to produce unstable results. As the noise becomes more consistant, the plasma eventually shuts off.. We replaced the Gernrator, one week later the same noise appeared and would shut off the plasma. We replaced the "D" style torch with the factory "thermo tulip torch". The noise went away for another week. when it returned we tried a new "EMT style" torch, and that lasted 2 weeks untill the rumble returned. After this "rumble appears the flame dances up and down and the results are very unstable and not useable for us.Anyone else having this problem or have any advise for this...?