Dear Motifator team,

My 5yr-old MOX8 GH keybed is not working properly. This just occurred a few days ago. It is acting very similar to this video: https://www.youtube.com/watch?v=HteWuBbDE_c

Same keys --- C combined with immediate lower G and F# combine with lower C#. The problem is present at all the octaves.

I tried to reflash the latest firmware version (1.02) but the problem didn’t go away. Before I attempt to open the unit, I would like to reflash the previous firmware versions (1.00 and 1.01). The link for 1.01 on this site doesn’t seem to work. And the Yamaha support website doesn’t list the old version.

If anyone is kind enough to share the links, this will be greatly appreciated!

Thanks!
Ritche

Welcome to the forum.

I doubt reinstalling older firmware will help what is apparently a hardware problem, but you should be able to download V1.01 here:
http://it.pcdrivers.guru/yamaha-mox8/download-678982.html

Hello 5pinDIN,

Thank you for the link!

I bought the service manual and decided to open the unit. I cleaned the contact pads and the flexible cable contacts, and then re-seated everything. I also did some continuity test on the GHK boards, to the cables and then to the keyboard processor. I did not find any obvious issue.

When I re-assembled the unit, the issue was still there. I reloaded firmware (1.02), executed keyboard check, then did a factory reset. It remained the same.

I probably did everything at least 4 times. The problem remained.

On my last attempt, I left the unit switched ON for a while. When I came back, surprisingly, the problem disappeared and the keybed was working properly.

So problem solved!

In the end, after seeing the design in detail, I don’t believe this is an issue with the firmware. I also don’t think this is a production issue (even though there are a number of people reporting similar problems both on the MOX and MOXF). What I saw though is a very basic electrical design problem.

I wish there is a way to voice out this concern to help improve the quality. The overall design itself is very good! The electronics assembly is really good quality, the keybed mechanical design is great! Not to mention sound-wise!

Thanks again for the link and the help!

Cheers!
Ritche

You’re welcome. Although I’m not sure exactly what’s going on with your MOXF, I’m glad the problem has been resolved, at least for now.