The crackling sound is coming from the burning end at the lens not near the laser tube itself. It makes this crackling sound at lower power settings. Almost like a high pitched soft buzzing. Kind of like a broken speaker makes as the coil rubs past the magnet.
Upon further investigation, the sound is mostly coming from the transformer. I took the cover off the LPS last night after posting the last video. That’s when I discovered the origin of the sound. So, I reinstalled the old LPS and it generated the same sound at low power. It goes away at around 5mA. Since I had it hooked up, I also tested the “IN” voltage and got 4.8 v. I’m guessing I prematurely replaced the LPS. It looks like I didn’t need to do so. I should have asked you guys before I started replacing items, again.
The crackling sound at low current is normal. My theory is that until the tube ionizes (4ma) it provides no load so the HVT crackles, corona, not a short, my guess.
At this point, I think we have exhausted blaming anything other than the tube.
Consider this; if you buy a tube and it does not fix the problem and an alternate problem is found you have not wasted your $$$. The tube is consumable and WILL eventually fail so you would just be ahead of the game… 
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Thanks guys for all the help. We’ll see what a new tube does for me.
Thank you!!
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