I don't have a MODX so I can't test that. However, if I have a Performance with only Parts 1&2, using multi-channel MIDI mode, only MSB/LSB/PC changes on channel 1 work. Not channel 2. Not channel 4. Not any other channel except 1.

Same setup if I am using a Performance that has Parts 1&2&3&4 populated then using multi-channel MIDI mode, only MSB/LSB/PC changes on channel 1 work. Not channel 2. Not channel 4. Not any other channel except 1.

It is true that Performance without SSS support exhibit different behavior. It cannot be explained by any advertised rule so this seems to be a quirk or unintended consequence. Something that you can exploit if you want. However, you have to program your Performances "special" to do this since hardly any of the presets are non-SSS in their natural state.

Here's the rundown of the quirk on Montage F/W 3.51 (I have a Montage, that's what I can test):

1) If Performance supports SSS (in Montage, only Parts 1-8 are used and none in 9-16) then multi-channel MIDI mode requires CH 1 for MSB/LSB/PC messages that change the entire Performance.

2) If Performance does not support SSS (i.e. has any Parts 9-16 as non-empty) then the MSB/LSB/PC messages are permitted to on any used Part for the purpose of changing the entire Performance. Any empty Part will not accept MSB/LSB/PC messages.

Examples (Multi-Channel MIDI mode):

Part 1 & Part 9 used (SSS not supported due to Part 9) - MSB/LSB/PC to change Performance can be sent to MIDI CH 1 or MIDI CH 9.

Part 1 & Part 3 & Part 4 & Part 11 & Part 15 used (SSS not supported due to Parts 11 and 15) - MSB/LSB/PC to change Performance can be sent to MIDI CH 1, 3, 4, 11, or 15 (any non-empty Part).

Part 1, Part 2, Part 3, and Part 4 used (SSS supported) - MSB/LSB/PC to change Performance must be sent to MIDI CH 1.

There doesn't seem to be any advertised rationale for this behavior so it goes into "quirk" territory. The common denominator is CH 1 always work no matter what.

BTW: it took a little bit of time to run through the testing because I wanted to use my tablet to send MSB/LSB/PC and all of the tools I had weren't quite right for this. Therefore, I wrote an iPad app to make life easy on me.

Yamaha has had unexpected quirky behavior in the past. Manny has posts of how he seeks out these corner cases in order to exploit these quirks to his benefit. I agree that one perspective could be to label these as "bugs" - but there's also a connotation (IMO) that bugs are things to be eradicated. Although I do think this would be considered a bug -- I avoided that label only because I think there's no real harm and there are corner cases where you can exploit this quirk in order to arrive at functionality that seems to exceed the original intent.

I think I would prefer to leave this "bug" alone allowing the OP to continue to exploit it and others another lever to pull in order to send MSB/LSB/PC.

As far as what I tested - I tested both MSB=62 Site List and MSB=64 Multi-Part (Performance) messages. They work the same, in Montage, as I have documented. This is why I generalized to state "MSB/LSB/PC to change Performance" which is meant to indicate either the Site List (MSB=62) or Multi-Part (MSB=64) messages.

Thanks for all the replies. Sorry its taken me so long to get back, the website just doesn't want to let me in other than on one specific browser on one specific computer. Very frustrating.

Bill, thanks for submitting this. im quite happy to live with it and as ive said, my workaround is the easiest and suits me.
I really came here to raise the 'why does this happen', as I know im using the correct settings. it could of course be the Fantom, but I figured by posting about it maybe someone else has seen this happen.

Maybe (ok, yes it is) using midi channel 1 is more reliable, but as I don’t need any SSS Performances, having to re configure two keyboard, over 40 Scenes on the Fantom is just too long winded.

It doesn't matter whether I have a part programmed on part 16 or not, I can call up any of the performances, as long as I stay away from SSS, but I just can't see why it would stop working completely. Ive tried tuning off part 16 on the Fantom, and of course this breaks communication with the MODX, so I know that it is mdii channel 16 working and no others.

The way I see it, im not calling up spcific Performances, im calling up a Performance slot in the Live set. Possibly this is where we are seeing different things? I know I can change what is in a certain slot and that new Performance gets called up.

Again, thanks for all the replies and suggestions etc.

The way I see it, im not calling up spcific Performances, im calling up a Performance slot in the Live set. Possibly this is where we are seeing different things?

No, I am testing both Live Set and Multi-Part Performance. The finding was they have the same (quirky) behavior depending if Parts 9-16 are used or not (this whole "SSS" vs "not SSS" thing).

I have a Montage, not a MODX. So my testing is limited to a keyboard that has a different way it handles SSS. Namely the range of Parts that would disable SSS is different. This may have consequences on the quirk. In other words, differences in my testing vs. your experience are likely due to having a different keyboard. That said - I haven't really seen wildly different results.

Since this is a quirk, the behavior is not described by any documentation. As such, there is some amount of risk involved in relying on this since the well intentioned bug reporting by other users may "fix" this working against you. At least for now with your current version of firmware it works like you want. It's also unlikely that this will be "fixed" although you never know.

I'm not really compelling you to do anything. My personal preference in this situation would be to reprogram the Fantom to target CH1 and modify the keyboard range on Fantom to prevent the keys from triggering the MODX tone generator. That said, I respect the stated aversion to that and you can certainly continue to add SSS-defeating Parts in order to allow MIDI Channels other than CH1 to respond to these Set List MSB/LSB/PC messages.