Many thanks @tbskoglund I wrote a reply to my own message and now see I got distracted and forgot to press “submit”. RESOLVED. A lower midi track on the Octatrack was set to to the same midi channel as the one I was trying to send program change from and the lower one was also sending a PC command. (on the Octarack midi messages from a lower number track have priority). And the OT midi channels send PC messages (if set) even if the track is not activated, which was the case, thus my oversight error. There were no cc messages set on the lower midi track, so that’s why the cc messages from the higher channel were received by the H9.

Many thanks for the quick reply, really appreciated. Great support.

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