M-Audio Fast Track c400 - Junk Item Thank you for viewing. The headphone jack and phantom power jack do not work. The MIDI and SPDIF jacks may work, but have not been confirmed. The headphone jack has very faint audio barely audible over white noise, so it's likely an internal contact issue. The lights illuminate normally. I'll sell it to someone who thinks, "I can fix this myself!" No returns or refunds, please.