Mmt8 - fixable. Works great until....?

Alesis MMT8 . Grey model. 1.11 OS. Bought off [eBay] about a year ago. When I tested it on receipt I’m pretty sure I recorded (and played back) a basic sequence from a motif so looked to be fine. No Paypal dramas…

So a year later - I pull out the unit. Original power supply, not even much dust on it and fire it up. It works fine. There was an old sequence and playing play had it go through to another synth fine.

All good - all great. Just…it won’t record in any MIDI data anymore.
Its crazy, all lights and buttons work fine. I’ve opened up, and no sign of physical wear or dust.

For the MMT8 owners/ex owners, its nothing more complex than selecting a SONG/PART, hitting record, choosing your track, hitting play and waiting for the countdown is it ? (I checked the manual). It says its recording - but I can’t see any event data.

It can’t be the cables, they work fine on other synths. Have used various controllers and even a mac with ableton to send midi data over to thr mmt8.

Can’t even find anywhere in the UK where I can get this fixed. Checked memory (100% available), LCD is fine. Click track ok,and no errors or indication something is wrong. Has anyone else heard of the MIDI IN interface simply giving up. Again - no sign of damage/dust etc.
Seeing this forum gives me some hope someone might have an idea of what chips need replacing.
Any help welcome.

Hi Mark, just saw this. Guess you posted a few weeks ago, and perhaps you have this figured out by now.

In any case, I’ve had an MMT-8 since they came out in the 80s (and have since acquired others). I still dabble around with one from time to time.

Just wanted to point out that the MMT-8 has MIDI input filters, and won’t record anything that its filters are set to ignore. (Apologies if this is obvious and you’ve already checked it out, but it was not mentioned.).

So… have you verified that your MMT-8 isn’t somehow inadvertently been set to, for example, filter out notes? Or, perhaps the memory got scrambled and the filters got into a strange state by themselves. Either way, check that all filters are off (go through the settings under the “MIDI FILTER” button) and try another recording test.

Speaking of scrambled memory, perhaps you should also make sure that your MMT-8 battery is okay. The battery inside is “permanent”, but will eventually drain. I believe nominally, at time of manufacture, the battery is supposed to be good for 10 years or so (although typically many last for quite a lot longer). Still, we are decades since manufacture at this point. To ensure reliable operation, it is probably a good idea to install a fresh battery, especially if you plan to start using your MMT-8.