One of Mushroomhead's three vocalists, Waylon Reavis, has just announced he quit the band via his personal fan page:
Due to irreconcilable differences with band ownership, effective today vocalist Waylon Reavis has severed all ties with Mushroomhead and Filthy Hands Company. Waylon is thankful for the opportunity Mushroomhead has provided him the last 11 years and will now be concentrating his time and efforts on another project. Thank you to the fans for all your continued loyalty and support throughout the years. There is no further comment at this time.
Reavis joined the band in 2004 after Jason "J Mann" Popson left. When J Mann returned to the fold in 2013, the band decided to let Reavis stay onboard but I guess that was short lived.
The band has yet to issue a statement on Reavis' departure.