I don't see anything wrong with the data files. I think what might be happening is you're latching on to a tower that's just close enough for the scanner to see the trunk signal, but too far away to receive the proper voice signal. This might happen if you're a fair distance away from one of the towers "first" in your frequency list - most likely Banker's.
What I would recommend is locking out the frequencies for all towers except the one nearest to you, and trying to scan again. To do that, you need to put the scanner in HOLD mode, turn the knob until you get to the frequencies, and hit L/O, then turn the knob to the next freq, and hit L/O again, etc.
Because I don't know where you are in the city, I'll give you the locations of the towers and you can choose what to run with.
1 (Banker's) - Downtown, 855 2 St SW
2 (TransAlta) - Coach Hill, 7700 blk Old Banff Coach Rd SW
3 (Spy Hill) - Far NW, 11200 blk 69 St NW
4 (Fish Creek) - Far SW, 16200 blk 37 St SW
5 (Forest Lawn) - East, Memorial x 28 St E
I would not recommend using the Airport tower as your primary one, because it is very low power and won't reach too far beyond the airport property. For completeness' sake, though, the tower is on top of the terminal building at the airport.