MXR Delay System 2 freeze

[Tav]

Hi there, My old Digital Delay System 2 yesterday broke down. It powers up but the display reads "0000", it does not respond to the time change pot.
After a few hours I powered it up again and suddenly it worked again, after 2 hours it froze down again and now it's down.
Anyone exprienced the same problem with a similar unit?