https://www.thomann.de/gb/rockboard_quick_mount_pick_box.htm
I snapped the end tags off as I'm no longer using a Rockboard pedal board. Just add Velcro to the bottom and fix to your board.
I'm loving mine.
It does sound huge.... So much bottom end.
I'm rolling back the volume control on my bass, adding chorus and reverb for that 1980s synth vibe.
I've had similar problems with various peices of equipment over the years.
I've had horrid sounds in the house and silence at other locations.
Unfortunately there is no cure.
Arrived today. π
Even at it's lowest settings I'm getting pure square wave fuzz. Mix it with a chorus pedal for early 1980s synth sound. Perfect for early Gary Numan / Tube way army.