OT2m and ID-5100

Hi all,

I thought I would dust off my long idle Tracker2 OT2m and try to get it back on the air. The ID-5100 can output its GPS data to it's DATA port, so I ordered Icom's serial data cable and am feeding NMEA GPS data to the OT2m. This part all works great!

I have the OT2m connected to a separate Icom V8000 and antenna for RX/TX. Unfortunately, I notice that the 5100 is keying up unexpectedly, seemingly when the OT2m receives a packet. Is it possible that data is being sent _out_ from the OT2m to the ID-5100, causing it to key up?

I thought perhaps it was the autobaud setting, so I disabled that. I also made sure I didn't have any digipeating settings enabled. Could it be something else?

I've tried to do my best to ensure there aren't any loose connections, or RF getting into the cables used for the setup.