My 396t was working perfect untill a few days ago . i listen to the local PD which is p25 digital , every so often it stops scanning and has a loud noise , like open squelch . it seem to do it on a random basis as far as group ID's are concerned . the open squelch noise will stay on untill i push the scan button or , let it sit there for about a minute then it will quit on it's own .. di i possibly change something in the programing by accident ? of maybe the PD's system is at fault ? of internal radio problem ? .. any help or comments are welcome .. Thx.