In both MPC standalone and desktop, the Sampler includes an input monitoring button which allows you to monitor the live feed of your audio source as it’s being recorded.
To hear your audio source through the sampler, set the input monitoring button to IN, as shown below:
MPC Standalone Sampler
MPC Desktop Sampler
Note: If you are using a Mac to run the Sampler in MPC Desktop, in addition to enabling the input monitoring button, ensure you grant the MPC app microphone access in your system settings.
To do this, select the Apple menu > System Settings > Privacy & Security, then click Microphone.
Turn on the setting for MPC, then restart the MPC application.
For more information on input monitoring and its role in the MPC, please click here.