This is due to a polarity mismatch between what the EX-P pedal is sending and what your connected device expects to receive.
To resolve this, flip over your EX-P pedal so that the bottom panel is facing upwards and toggle the switch shown below...
If for any reason the this does not resolve the issue, please try the alternative troubleshooting options below:
1. Power off your connected device, connect the EX-P, and then turn the device back on.
2. While your device is already switched on, connect the EX-P.