Gigged 2 weeks ago and when on a user patch I noticed scrolling going on in the LED display panel and the different effects were coming in and out. Once I switched the unit off and back on it was ok.
Last week there were no signs of this problem.
At a gig this Friday the same thing happened twice and again last night....only the once and this time just a slight flicker in the display which then it sorted itself.
I have not dropped the unit, nothing has been spilt on it and i have taken the casing off to check for dust but it is clean as a whistle.
Could it be a fault with the power supply? Do the pots need cleaning and if so, how do I do this? Could it be I am changing the bank and patch pedals too quickly when scrolling through to get to a user setting I have programmed?
Any ideas?

Do you mean (1) the screen was on/off/on or (2) the data on was actually moving?

1/ could be something faulty in the power connector, the power supply or the screen itself or its connection.
2/ bug on the prowl.

The scrolling was in display screen and each effect that showed came on for a split second.

A bug on the prowl? No bugs can get in the unit.