I have a trunk tracker IV and have my local apco 25 police tuned in. It,s in the 700MHz range. My problem is this, I can see on the screen that it is scanning the range, but i hear no audio at all ? Somtimes i hear birdies, but not all the time. I,ve got the scanner on hold, and if i turn hold off it will automaticly jump to a different system. I would greatly appreciate it if someone could help me with this matter. Thank,s, Bob in Alaska.