Just got it last week from Anon-Co, manufactured in March, firmware shows up as version 9904e. Everything works as expected so far, except there is a static noise at one position on the volume knob. Happens across all bands, modes. Tried turning the knob through its full range back and forth for a minute, tried changing the battery. At this one spot, it just cruds up the audio! I'm hoping I don't have to open this thing up and clean it (assuming the problem is factory gunk). Has anyone had this problem with a brand new portable before?