Turned on my MOX8 after a couple weeks and it’s doing this thing where it starts repeating (kind of like a really simple arpeggio) on certain keys if I hold it down for more then one strike.  I unplugged the sustain pedal and it’s the same. It’s basically just stuttering on one note at a time and not every note. But seemingly only when I’m playing a chord and holding the key down manually.

It does it in all modes, though not on every Perf or Voice or Song. I will keep trying to isolate it, but I’m hoping someone can jump in and help me.

I did factory reset. And it’s doing the same even in default factory.

I’m worried it’s from dampness, but not sure how I can do anything about that at this point. Would a complete OS reload be of any help?

Trying to isolate the issue. I think I have a little more info. It seems to be happening only around middle keys, D especially and sometimes C. And the note it causes to stutter is NOT the note being struck (and held) it’s setting off another note. Like when the middle D is int the chord it starts stuttering on Ab. Which isn’t even the chord at that point. But, oddly, when I then go ahead and push down that errant Ab the stuttering goes away, like it’s “satisfied”. It’s usually middle D causing an Ab but it also sometimes sets off Eb, one tone above.

It feels like something do with arpeggiation, but maybe just cause the stuttering sounds somewhat rhythmic. And also because it only happens playing a chord, which makes me think of the arpeggiator trying to “do” something.

I played with the velocity settings, to see if it could be somehow related or at least give me a way to limit the occurrance, but it’s seems to not be affected by velocity unless I play SUPER SLOW/SOFT, then it doesn’t do it.

The one for sure is the chord—it’s only when there is more than one note play along with the D or sometimes the C. And the stutter is almost always on Ab, but sometimes on Eb.

Hi.My reply may not be useful but did you try to look at the arp settings also?

I haven’t changed any arpegio settings. It’s happening on Voices that aren’t assigned an arpeggio, but in Performances that do HAVE other instruments playing arpeggios that are being triggered. So, yes, it seems related, but the Perfs play fine until I do as described above, play chord, play a D or C and hold it.

I guess you already unplugged everything already:

USB cable
Expression Pedal
Sustain Pedal
All outputs, except one to monitor yourself
Controllers, Mics, Instruments

You also turned off the Master and Insert Effects, turned off the Arpeggiator (and experimented with ARP-EDIT menu).

I know.these are all obvious, but sometimes we oversee one of the obvious solutions!

You can also try a controller-monitor plugin in your DAW.
Trigger the problem and check if unwanted controller data are also being sent.

Too find if it’s moist or other damage to the keys, you could switch off local control and send MIDI from your computer or other controller.
Just make sure that your MOXF isn’t set as MIDI in if you try from your DAW.

Best of luck!

I don’t use DAW, work only with MOX synth. Wish there was some other way to accomplish the MIDI troubleshoot, cause that would definitely show whether it’s a contact issue at the keybed or something else.

Would anyone recommend/dissuade me as to possibility of opening the MOX up to perhaps clean the contacts?  I have no real options when it comes to qualified repairs. Or should I just leave “bad enough” alone? I suspect it’s moisture or dirt on contacts, since it’s improved somewhat from leaving it on for a couple days. Maybe I need to stuff some silica bags in the thing!

Anyway, thanks for tips. And any other feedback is appreciated.

For testing purposes, you can play a MIDI file from a USB stick.
Or maybe you already have some song saved internally in the MOX from before this issue started that you can play to see if the issue is there too?
At least if you know it is damp in the keys causing this, you’ll know what to focus on when opening the keyboard.

Best of luck!

Thanks. Yes, I will try that. Although it’s tricky because it only does it in certain keys/chords (when I’m playing anyway in certain keys, using certain actual keys) and only in certain combinations. And still not 100% certain cause It never does it when I’m play a single note. Has to be a chord and only certain inversions of that chord, particularly if the notes are within three or four half steps of each other. And, like I said, If I hold down the physical key for the errant tone that’s being sounded, and then play the same chord, it goes away. Would think that would be a clue. 

I wish there was, for temporary fix, a way to do away with the physical keys and/or the tone generator for those notes. But I suppose it doesn’t really work that way or that simply.

try this:

Record in your DAW a midi track, using an intern DAW-VST Instrument. Input the midi data (a chord, or a combination that usualy trigger the problem) with the pencil, rather than with the MOX. Play them back through the MOX.
Is the problem still there?

In this was you’ll bypass the MOX’s internal tone generator (since you are using another VST-Instrument...for example the Halion Sonic) and also will not use the MOX’s keys to input the midi data.

Tell us hat happens!

If you set local control to off, you have broken the connection between the keys and the tone generator. If you then play a MIDI file from USB or internal sequencer you should be able to test without a DAW.

Thanks for all the ideas.  To complete this thread: The problem was almost certainly excessive humidity. (I live in Central America). After a few days, and slight relief in local rain and humidity, it stopped doing the weird stuff. So pretty obvious correlation there. I’d already found a Yamaha technician a two hour drive away, so I brought the keyboard to him anyway to have him inspect it and if nothing else was found, just clean it it up inside. He said it all looked fine. Fixed a wobbly key and put it back together. Meanwhile, though, I went ahead and bought a new MOXF6. Need a back up, so now I’ve got two MOX’s. Have to get used to the action (or lack of same) on the MOXF6.

I agree...mine was doing same thing...when I was playing outdoors after a rainstorm in very high humidity....I know exactly what you are talking about…