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Blinking LED lights and crackling/popping when FX is turned on?

Hi all,

While I am having a blast playing my Pro 3, I found it to have a couple of issues:

1- The LEDs and backlit buttons blink seemingly randomly out of nowhere! This seems to happen mostly in the 3 LPF selection buttons, but I also seen it happen in the velocity buttons and other LEDs. They just sit there blinking out of nowhere. Not sure what goes on. It seems to also blink more whenever I move the Cutoff potentiometer.

2- Whenever I turn on FX, even without loud sounds, I can hear clicks and pops that essentially make the FX useless! It becomes really apparent when the cutoff is low. This doesn't happen in my Prophet 6. This happens even if the FX Mix is at 0. It's like there's some clipping going on, but it happens even on quiet sounds with just 1 oscillator!



I am in the latest update. Is there something I can do, or should I go for warranty?

Re: Blinking LED lights and crackling/popping when FX is turned on?
« Reply #1 on: April 02, 2021, 01:19:59 PM »
Just realized there is one new update (1.1.2.8) that I haven't installed. Let's see if it fixes it!

Re: Blinking LED lights and crackling/popping when FX is turned on?
« Reply #2 on: April 04, 2021, 11:36:42 AM »
Unfortunately none of those issues are fixed in the latest update (1.1.2.8)




Re: Blinking LED lights and crackling/popping when FX is turned on?
« Reply #3 on: April 08, 2021, 06:06:49 PM »
1- The LEDs and backlit buttons blink seemingly randomly out of nowhere! This seems to happen mostly in the 3 LPF selection buttons

This is likely caused by a minor hardware issue on the part of the circuit which sends data to/from the front panel.  On some units, one of the ~500 or so resistors on the main board had the wrong Ohm value, which can lead to blinking filter LEDs and knobs which detect motion when there was none.  Basically, the resistor filters out random electrical noise to produce a clean signal, and the filter isn't quite strong enough on some units.

To fix it, contact Sequential's support team.  It's easy, but may require opening up the synth to swap out a part.

This is just my personal theory, but I suspect it may also be possible to fix by using a filtered or conditioned power supply.  Basically, eliminate the source of the electrical noise and it might stop the symptoms.  Haven't had a chance to test that though.  It just seems plausible that the reason the issue wasn't caught sooner was because the QA testing facility might have really clean power supplies and the issue requires dirty mains power in order to happen.  But take that with a grain of salt, since it's only speculation.

Re: Blinking LED lights and crackling/popping when FX is turned on?
« Reply #4 on: April 08, 2021, 06:12:09 PM »
2- Whenever I turn on FX, even without loud sounds, I can hear clicks and pops that essentially make the FX useless! It becomes really apparent when the cutoff is low... This happens even if the FX Mix is at 0. It's like there's some clipping going on, but it happens even on quiet sounds

I've run into that sometimes too.  I haven't found a universal way to resolve it completely, but it often seems to help if I lower the VCA envelope amount... to reduce the volume of the signal going into the digital effects.

Or sometimes, lower the levels in the mixer section.  But that's more to avoid clipping in the ladder filter.  Effects are later in the signal path, so VCA env amt is probably more relevant.