MAXX1044 Noise Photon Vibe

[Technatured]

I’ve got a Photon Vibe that went together just fine, but seems to have that terrible oscillation noise I’ve heard of. I’ve tried several MAXX and a TC1044SCPA with the same problems. I’ve had one other issue before with MAXX chip on an FZ-1A build, but switching it out with a TC did the trick so I didn’t look into it any further.
I’ve noticed physically touching the chip makes an audible change in the frequency which I find odd. Using the pedal without the voltage doubler works just fine, but with lower bulb intensity and re-biasing. I’m considering using it with an external voltage source of 18v to see what happens. Maybe replace the filter caps first if that goes just fine?
One last thing. I’ve gone through the data sheets, and these chips call for pin 5 to be grounded when in doubling mode, but the schematic shows it unused and ungrounded. When I get a chance to get back to the bench it’s also something I plan to try.
I understand info is limited at the moment, but any insight is appreciated.

 

[falzhobel]

Is your 1044 from Mouser ? I had trouble making them work in Isoceles boost. The Tayda one seems to be ok.

 

[Technatured]

I don’t recall, but do believe I got both MAXX and TC chips from them at one point. I don’t use them often, so I’d imagine rolling through my small stock might be worth a try. I’m guessing you’ve had problems with a 1044, but the “same chip” from a different vendor/batch did the trick?

I’ve read about issues like this when researching voltage doublers and inverters, but this is my first run in with my own problems.