Yamaha 01V Owner's Manual page 63

Releasing Input Channel Pairs
1. Press the [SEL] button of both input channels simultaneously.
OR
On SETUP page 4, use the cursor buttons to select the paired channel
switch, and then press the [ENTER] button.
The following dialog box appears.
2. Select OK, and then press the [ENTER] button.
The stereo pair is broken, and both input channels operate independently.
Pairing Input Channels
01V—Owner's Manual
53