Same thing here - Pro x 2nd time I turned it on - no sound with the L6 link. Got it to work - unplugged the L6 at my DT25 - Turned the DT back on and then plugged in the HD pro x that was already on. It worked but was very frustrating. Thought it was me - Thinking of bringing my old pedal to rehearsal tonight. Must be the DT25 no syncing properly.