sidesmusic

I had the same problem with my DL4, hiss / loud noise when the effect was activated so true-bypass (alternate is always present) connected mono (L input / output L). With a cable disconnected on R output the hiss disappeared. I cleaned pcb and all components with the spray and checked the solders and they were good but the problem remained. I kept turned on the unit for more than several hours at a time (do not remember if 18 hours) and the hiss / noise disappeared and is no longer returned also connecting in mono (L in / L out). I have no idea why this worked but it's what happened to my DL4. I hope it can be useful.

you can play this chords and record them on the DL4 loop sampler, reverse play and use the button "play once" and will correctly on timing if you play it live with a band.