The same problem has come up with both of my DL4's.
While in the loop mode and the mode is turned off, it's recording. I can hear a churning and when I twist the delay time knob, the sound changes pitch. Done the factory reset on both and it still persists.
When I go into any of the delay modes, the churning stops when I turn the effect off and it resumes when I go back to the loop mode.
There'll be more experimentation in the next few days as this came up as a buddy was coming over to jam and I didn't want to futz with it then. Will see if it matters what pedals come before or after, etc...
Could the pots need replacing?
One DL4 was on my pedalboard for a gig in mid-March and there wasn't a problem then.
One difference between the gig and last night was the power supply - the pedalboard is juiced by a Voodoo Labs Pedal Power 2+ and last night I was using a Power-All PA-9 with the 11 connector daisy-chain (though only 6 pedals were being use). Wonder if not enough milliamps to the DL4 could be the problem...
And, it's almost moot - I was trying the TC Electronics Flashback delay which has a loop function. There's no half- or double-speed function but has the sound-on-sound and it's a quarter of the width of a DL4 so seriously thinking about getting one (or two) of those to replace the DL4's. I have a TC Hall of Fame reverb and love it.
the other ted
Or would you sing somethin' different. Somethin' real. Somethin' *you* felt. Cause I'm telling you right now, that's the kind of song people want to hear. That's the kind of song that truly saves people. It ain't got nothin to do with believin' in God, Mr. Cash. It has to do with believin' in yourself. Sam Phillips, "Walk the Line"