Test the instrument input cables. Inspect each instrument cable for defects, such as nicks or loose plugs. Plug the cable into the mixer and into an instrument. Turn down the instrument's volume completely and listen in the headset for any static or buzzing. If any is present, do not use that cable.
Test the effects pedals. Plug in effects pedals and listen for any residual distortion or feedback. Play an instrument and look at the sound levels on the mixing board or on the digital-recording software for spikes into the red. Replace old batteries in the effects pedals. If noise persists, the effects pedal may not be able to be used in recording.
Play a dry run or record a scratch track. Play the song or riff as it is intended to be recorded or record the song or track on a scratch track, meaning a track that will be erased. Watch the recording level indicators throughout recording and playback for spikes entering into the red level. Adjust the input volume as necessary to eliminate red lining during recording and playback.