Dave Smith Instruments SYNTHESIZERS

Hi Everybody,
I got a new Evolver last week, version 3 was on it when i got it. I'm having a strange problem.
Every now and then i when i just have a sequence running i get loud white noise which 
doesn't go away no matter what i do.
When i go to a different program the noise remains.
After power up everything is normal again.
I got no MIDI attached to the Evolver when this occurs.
This is scaring me, please help.
Many thanks
Es