When having two keyboards of the same family connected - sometimes you would need to change the MIDI addressing by using MIDI device numbers (instead of omni). That said, the MOXF6 should be able to work when it is connected alone. If that isn't working - then there is also another issue with the setup. That would be my first assumption (as was yours) before suspecting the USB hardware.

A typical suggestion at some point would be a factory reset. So perhaps backup everything on your MOXF6 so nothing is lost should you do a factory reset.

Although before doing a factory reset even - I expect a primer for all of the pertinent settings is coming ...

Make sure the firmware in your MOXF6 is up-to-date. Current is V1.12
Several MOXF updates have concerned iOS connectivity.
Press the [UTILITY] button.
Press the [JOB] button.

Wow, two quick replies! Thanks!

Yes, my firmware is 1.12, (Boot version is 1.01).

I'm not trying to connect both synths at the same time, so I can't see how it could be a device number clash. Both are set on on MIDI channel 1 and device 1.

I've backed up (ALL) to a USB stick - that side of USB works fine, it's the 'to host' side that has a problem - so I can do a factory reset. Just want to check that doing one won't wipe my flash memory.

Since my first post I've also tried connecting the USB of the MOXF6 directly to my PC. I do that a lot with the MOXF8, but I hadn't tried it with the 6 before. I have the Yamaha Steinberg USB ASIO driver installed, which works fine with the 8 and with my usual audio interface (a Steinberg UR816c). Unfortunately the PC doesn't recognise the 6 when I plug it in, which makes me more suspicious that there's a hardware issue.

When I say the PC doesn't recognise it, I mean that when the 8 is plugged in I see it in Device Manager under Sound, video and game controllers as Yamaha MOXF6/MOXF8 and as Yamaha Steinberg USB Composite Device. When I unplug that wire from the 8 and plug it into the 6 those entries disappear.

There are some tips here although the entire discussion doesn't apply since the user here has a different "flavor" of PC (mac). I offer it because the MOXF-side configuration applies:

https://www.yamahasynth.com/ask-a-question/usb-i-o-suddenly-not-working-on-moxf

Here's another checklist:

https://forums.steinberg.net/t/an-amateur-guide-to-connecting-and-using-the-moxf8-in-your-daw/146678

Given you've already compared the two keyboards for settings - I doubt the above will help.

Keep in mind that Windows USB can be tricky sometimes. Some versions of Windows have limits on the number of devices you can have and sometimes they get "used up". So uninstalling the USB driver (for the Windows-side driver) and reinstalling can be a way to "free up" or reset Windows to make a new device work. Now that Windows 11 is out (not saying you're using it) - there may be even more surprises.

I'm with you, however, that whatever is happening in Windows looks like what's happening with the iPad so it's probably not a Windows issue when testing that side of the fence. Also, iPad wouldn't have the same problem(s) as Windows has had historically.

As far as factory resets affecting your flash - read the docs and guides. There is information out there to guide through what's necessary to restore flash after a reset. I've seen suggestions to remove your flash card before updating. It's one way to do it. You would need to save an ALL file "without samples" which would be used to restore the MOXF to recognize the data on the flash card after you reinsert it.

If a reset is going to happen (and I'm not sure that's needed yet) I would do USB connectivity testing after the reset but before restoring any save files. This way you experiment with a factory reset instrument instead of one with your old configuration loaded back onto it

I'd also make a lot of save files before the reset. With samples. Without samples (both files). I'd cover all the bases I could and inspect the files on a PC to see the file sizes and make sure they're reasonable (not zero ... with samples should be larger if you're using the flash, etc ...)

Even if you don't initialize your instrument - it would be a good idea to make a backup just to do it assuming you haven't made one in a while.

HI Jason,
Thanks for your help.
I did read that first thread before I posted - googling 'MOSF6 USB not working' brings it up near the top of the list. That was what prompted me to post in this forum. His situation seems slightly different from mine, not just because of PC/Mac but because in his case it seems he *could* see the synth as a USB device in his DAW, but not pass audio to and from it. My MOXF6 doesn't even register as a device, plus it's program data (which I presume is Sysex) that I'm interested in, not audio.

Thanks also for the advice re:backing up. I'm going to hold off doing a factory reset for now: I have rehearsals leading to a tour starting next week, 90% of it is all programmed and ready to go. I have a handful more songs to set up, then I just wanted to rearrange the performance order to match the set list.and I thought the Performance Editor would be a quick and easy way to do it. Initialising and reloading would be a tiny risk,- I do keep backups anyway - but losing all that prep at this stage would make me cry like a tiny baby so I think I'll stick with programming from the panel for now!

But it would be good to get this to work properly for future use, so I'll keep trying things, and if you have any further Ideas, I'm all ears.

Cheers,
Gerard

Good _LUCA = Apple Lightning to USB Camera Adapter

NG _ Lightning to USB = Lightning to USB

You do say you are using the “adapter” but never mention the CameraKit - why it would work on the XF 8 and not the 6 (I don’t know, but Apple cables and adapters change over time).

If neither your computer nor your iOS devices are seeing the XF6 via USB, it could be a hardware issue. We’re sure you have activated MIDI I/O = USB
Continue your troubleshooting focusing on the USB “To Host” port of the XF6.

Yes, I have the Apple camera connection kit, this one:

https://www.apple.com/uk/shop/product/MK0W2ZM/A/lightning-to-usb-3-camera-adapter

I agree, I will continue investigating the 'to host' port. I wonder whether Yamaha UK can sell me a replacement internal USB board.