Hi,
I just purchase a pocket POD today and I have the exact same problem. At first, it works fine but after about 2 to 5 minutes, static comes gradualy and build up to a point where it is realy bothering and the guitar sound is fuzzy. This noise appear with batteries and also with AC adapter. the sound is still there if a USB cable is connected between the POD and a computer wether a guitar cable is connected in "guitar in" or not.
That is not a cable problem : I have tried several cables, all working fine with the other piece of equipement I own, one of them being a POD XT Live.
I'd like to know if you encountered this problem beside the post at the top of this topic? And is it a case of replacing the unit?
Thank you for your help