« Reply #3 on: December 20, 2023, 05:12:50 PM »
Sorry for delay in reply on what the fix was.
Context:
My PX is on f/w 2.2.2 and I had some strange USB related issues (showing up as 'red' in Ableton live - I'll try to post a picture of this). But the main problem was the PX would stop playing audio after a random period of time (more than 1 hour of power on).
I had got some support from Sequential who told me how to:
This is an issue we have been tracking, and we have determined a couple of solutions that should get your Prophet X back into good shape. The first and most important is to adjust the internal PSU for slightly higher voltage. If you're handy with a digital multimeter and have access to one, it's actually a relatively simple procedure. You need to take some care in the presence of high voltage, but the adjustment only requires the DMM and a small insulated screwdriver. I attached the instructions to this email so you can have a look.
The other solution involves updating the BIOS on the mother board. You need to make a bootable thumb drive to insert directly into the mother board, a USB keyboard, and an HDMI monitor. The process is pretty simple and essentially removes the need for battery backup on the mother board (this has less of an effect on booting, but still helps.)
I had done these actions, which seemed to help for a few months, but then the problem came back.
I solved the USB issue with a new hub and cables (yes, one of the USB portsin my computer was dodgy as was one cable!)
So, then after discussing my journey with ART, their approach was to repeat the steps I had done to ensure they were done correctly. They reported that the voltage was again low (not at the 5.2v I'd set). Since I've got it back, it has been solid.
Conclusion:
Main cause seems to be power supply voltage drifting and getting too low.
Aux causes are poor USB connections which the PX is sensitive to and
CMOS battery can drain fast so the BIOS update should resolve that.
Several things to try here. First (and likely easiest) is change out the cmos battery. As I recall it's a readily available 2032. Next check the 5v output on the computer power supply (only if you're comfortable with doing that sort of thing). I don't know which lead is the 5v one but with the power on you can go through them one by one and find the 5v output. Not sure how to set the voltage level but Sequential will know and will help you for sure. Be aware that there may be high voltages present. You could also try booting with a usb keyboard plugged in. This is how to do this from Sequential support:
If the unit is not booting:
A. Resetting the Motherboard
Plug a wired computer keyboard into the rear USB sample loading port.
Power on the instrument. When the loading bar gets close to full, press F1 on the computer keyboard. If nothing happens, wait a few minutes and press F1 again.
After a few minutes, power the unit off and on, and see if there is any change in boot progress.
Note: some keyboards require holding a function key (Fn) to enable F1-F12.
« Last Edit: December 20, 2023, 05:20:36 PM by thirteen_engines »
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Prophet X, Prophet 6, Nord Electro 5D 73, Korg Wavestate, NDLR, Arturia Matrixbrute, Waldorf Iridium, BARP 2600, Eurorack and altogether too many guitars.