Pod HD300/HD400
Factory Reset:
Hold down the A footswitch while powering the unit on. Press the PRESETS knob, then press it again.
Video Tutorial
No Global Settings reset
Pod HD/HD500/HD500x/HD Pro/HD ProX
Global Settings Reset:
Run Line 6 Monkey with the HD500X connected via USB. Highlight FLASH MEMORY and click REINSTALL LATEST (or INSTALL LATEST if Monkey shows that you are running older firmware). Make sure to back up all of your presets and setlists beforehand using the HD Edit software.
Factory Reset:
You must reinstall the firmware, when Monkey prompts you if you want to keep your existing presets, hit no.
Video Tutorial
Safe/Pedal Calibration Mode:
Hold down the right arrow on the navigation button while powering the unit.