Also, it would help to know what system(s) for the conventional frequencies are giving you problems. Either provode a link to the database page (or pages), or at least give their names (city, county, agency, etc).
You might also attach your FreeSCAN file to a post, so somebody can take a peek and see if anything appears out of place. Since the *.996 file format for FreeSCAN is not an acceptable file extension for upload on the forum, either compress the file first using a file utility such as WinZip, or 7Zip, then attach the zipped file. You can also simply add a second extension to the file name. Example: If your file was named kubik1981.996, then save a copy as kubik1981.996.txt and attach that one.
If you are using the standard whip antenna on your scanner, and are getting the 'locked up' symptom indoors, remember that you may be getting interference from one or more devices in your house. PC's, monitors, wireless hubs, broadband modems, and some printers all produce noise that will interfere with a scanner, especially at close rane. One of my photo printers really stalls out several of my radios, causing them to stop on one of several frequencies as if somebody was "dead-keying" a mike, unless I move them away from that printer, or use an external antenna.