I’m controlling the GR-1 over DIN MIDI from my LinnStrument. With MPE enabled, I’m noticing a problem with my pitch bends. If I stay on one note but wiggle my finger around, I’ll hear it intermittently bend down the full bend range (-12 or -24 semitones, depending on how I have the GR-1 and LinnStrument configured). It jumps down for a moment and then back up to the current pitch. Otherwise, bending works as expected- I can slide my note up or down on the LinnStrument and I’ll hear the GR-1 bend the appropriate intervals.
I’ve tested the LinnStrument with other synths and checked its output on a MIDI monitor, just to make sure there weren’t any stray pitch bend messages telling it to jump down and octave and back. Everything checks out correctly, and it is only with the GR-1 that I have this problem.