Significant Hum When MIDI Connected on Yamaha CP40

by Cayce
(Ringwood, NJ, USA)

Hello, Yamaha Keyboard Forum;

I have a CP40 connected in the most basic configuration for both MIDI and audio input into Protools. In the MIDI track, I get the MIDI input fine, triggering my Kontakt 5 instruments. In my audio track, for recording the CP40 as a DI audio instrument through the R/L outputs, going into a PreSonus interface, I'm getting a significant hum that only goes away when I disconnect the MIDI cable. I've tried various cables on both the MIDI and audio connections, but the hum persists. I'd like to have this connected both ways for easy access when changing from audio to MIDI recording, but as it is, I have to disconnect the MIDI cable to record clean from the Yamaha CP40 audio outs.

The hum doesn't respond to Master volume or any other settings, except to slightly change intensity when I toggle through different voicings.

Any suggestions would be appreciated.

Thanks.

Cayce