Mod wheel on MODX8 activates itself after a few seconds.

Please explain what you mean by 'activates' itself.

1. the performance and parts have NO mod wheel assignments but when you move it the sound changes?

2. the performance and parts DO HAVE mod wheel assignments but the wheel moves back and forth on its own with no one touching it and makes the sound change.

3. the performance and parts DO HAVE mod wheel assignments and the wheel does NOT MOVE at all but the sound changes exactly like it would if the wheel did move.

Which of those actions is what you are experiencing?

After it activates there is no way to turn off the vibrato however I position the mod wheel.

If that is true it means the position of the Mod wheel is NOT is not being sensed and sent to the software control. That would indicate a problem with the position sensor or the mod wheel itself.

There is a Controller Hold/Reset setting on the Utility -> Settings -> Midi I/O screen (page 191 of the reference manual) that determines whether controllers, including Mod Wheel, will reset to their default value or HOLD whatever their current value is when you change performances.

The default value is RESET and for the Mod Wheel that means its INTERNAL position will reset to minimum. But the PHYSICAL position will still be whatever it was.

So when the next performance loads and logical position is ZERO but the physical position is NOT zero then when the wheel moves the value will jump from zero to match the physical position.

If the wheel is loose the slightest touch, or vibration, can jar the wheel and cause it to move slightly. Or your pounding on the keyboard will vibrate the instrument and cause the wheel to move.

REMEMBER - a minimum position for the wheel does NOT necessarily mean a ZERO value. When you make control assignments you also assign a curve type and a polarity Uni/Bi. Those assignments in combination with the wheel position determine the actual value sent to the control software.

I suspect the mod wheel is loose and vibration is causing it to jiggle slightly when you begin playing a new performance.

Took it to a shop and they tried a bunch of things (aside from hardware repair) but can’t figure out the problem.

Why didn't you have them repair it? If the wheel position isn't being sensed it needs to be repaired. If the wheel is loose it needs to be repaired.

At a minimum you need to be able to physically move the wheel to minimum to eliminate any effect. If you can't do that it needs to be repaired.

Backup your keyboard (save an X8A file) then do a factory reset if you haven't done this already.  

Then I would connect to a computer, run MIDI-OX or some kind of MIDI monitor and see if MODX is sending modulation messages when the modwheel is moved.  Make sure the MIDI mode is changed to USB if that isn't the default.

Posted by: Andrew

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3. the performance and parts DO HAVE mod wheel assignments and the wheel does NOT MOVE at all but the sound changes exactly like it would if the wheel did move.

It behaves as such. Thank you

Posted by: Andrew

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Why didn't you have them repair it? If the wheel position isn't being sensed it needs to be repaired. If the wheel is loose it needs to be repaired.

At a minimum you need to be able to physically move the wheel to minimum to eliminate any effect. If you can't do that it needs to be repaired.

The tech said that he opened it and found nothing broken, so he did not try to replace any piece of hardware.

Posted by: Jason

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Backup your keyboard (save an X8A file) then do a factory reset if you haven't done this already.  

 

Then I would connect to a computer, run MIDI-OX or some kind of MIDI monitor and see if MODX is sending modulation messages when the modwheel is moved.  Make sure the MIDI mode is changed to USB if that isn't the default.

Will try and post an update, thank you!

The tech said that he opened it and found nothing broken, so he did not try to replace any piece of hardware.

Thanks - you had said they didn't try to repair it so I thought they hadn't opened it. Sounds like they didn't find the mod wheel to be loose.

I reread the thread and wondered about this.

After it activates there is no way to turn off the vibrato however I position the mod wheel.

Typically the mod wheel wouldn't cause vibrato unless it was moved back and forth. That is because it would be assigned to 'pitch'. Then if you move it the pitch changes. But for vibrato it would have to move back and forth.

Maybe there is another assignment that is changing the pitch? Is this a preset performance? If so which one?

You may need to use a brute force, trial and error, approach.

1. how many parts does the performance have? Solo each part one at a time to find the problem part

2. how many elements does that part have? Solo each element one at a time

3. at the performance level change the filter type to ALL and check every destination to see if 'Pitch' is assigned.

4. hold the mod wheel to keep it from moving - does it still produce vibrato?

Just throwing things out there to try. If you provide more details about the performance and each part type (AWM2, FM-X) and their number of elements maybe something else will come to mind.

Arpeggios and motion sequences can also cause vibrato so you need to check those also.