Air Conditioner NOISE

We just completed our FIRST long stay in our TM 3023 (2004) that we bought last fall (10 whole days with 2 kids and 2 dogs!). I think I have figured out where to put everything and it is truly a treat after camping in a traditional popup.
One "surprise" was the noise level of the AC, even on low. We have a small TV and had to have it turned up almost all the way just to hear it.
Is this noise level a common complaint, or do we possibly need to have ours looked at?
Any advice will be greatly appreciated - we are hoping to get a lot of use out of this camper!