Same problem with my JVM410H.
I asked Sonicsam a "step by step" tuto.
Ok, I posted this to Rock666 but maybe this will help here also :
- check your midi connenction (from out on the FX8 to in on the JVM)
- are they on the same midi channel (default channel 1) ?
You can reset the JVM to listen to channel 1 by doing the following : Switch the amplifier off (Power switch, not Standby).
Press and hold the FOOTSWITCH / MIDI PROGRAM switch.
Switch the amplifier on (Power switch). Release the FOOTSWITCH / MIDI PROGRAM switch, the LED will start to flash.
Send ANY MIDI command using your FX8.
The amplifier will detect which channel came in and configure itself to listen to that MIDI channel only.
- check on the midi page of the i/o setup menu : midi channel 1, Prog change On (I'm not sure this is necessary, but that's how I did it...)
- in stompbox mode go to the cfg page and scroll down to Midi PC and select the desired MIDI PC number (also check your midi channel again on that same page...)
Put your JVM in Midi Program mode and then turn the Value knob to change the PC (say from 0 to 1 as an example) you will transmit that last PC nr to the JVM (midi led flashes rapidly for a few seconds)
- Save your preset !