Proper dispensing is a balance between temperature, pressure and line resistance. Your ambient temperature is fine, as long as cold air is getting up into the faucet tower, too. If the faucet is cold, then you're probably ok on this point.
The inner diameter of the tubing determines its resistance. In the simplest terms, line resistance should equal the carbonation/dispense pressure. That number can be refined to account for how high the faucet is from the keg and for better flow, but I'm keeping it very simple.
3/16" ID Vinyl tubing gives the greatest resistance while still allowing a decent flow, for home kegs. It is just about 3 psi of resistance per foot. Five feet of this size should be correct for 13-15 psi of dispense pressure.
Most homebrewers back off the pressure when confronted with foam, when the need is actually to turn it up. This only flattens the beer or makes the drinker have to fiddle with releasing and charging the headspace for each pint. Big PITA.
As you're adjusting pressure, give the beer some time to catch up. About 15 minutes for a major change of 5 psi or more should be sufficient.
If your tubing ID is larger than 3/16, the dispense pressure will be lower. There are a lot of charts and articles that detail line resistance.