Aircon / Vents acting up

[Sike]

I noticed the other day that the vents on the passenger side wasn't blowing out cold air like it should, i was thinking that meybe the aircon needed to be regassed. But today i borrowed a piece of kit from work so i could check the temps coming from my vents and noticed a 5 degree difference between drivers side and passenger side. Drivers side got down to 5c so i was happy with that but when i checked passenger side it only got down to 10c? What could be the problem
Also i noticed the temp goes up and down all the time by a couple of degrees, so it will go do to 5c for about 10 seconds and go up to about 8-9c for about 10 seconds and go back to 5c, is that normal??

[Chris SRi]

Not sure if the vents are supposed to be different temps, but I'd guess the temp fluctuations is due to the compressor kicking in and out.