I would guess that if you have talked to the Technics support people that have had you do a hard reset, and probably install all the latest OS upgrades. If that is so then it leaves you nowhere.
One thing comes to mind. unplug all your pedals and do a reset and try it. If that does it then you are on the right track.
If not take it to the shop.
Best to you and welcome to the forum
Bebop