I just had mine repaired for that. It was a cracked plastic condensate pan under the air conditioner. It would also drip when it rained (depending on wind, etc.). You may also want to give the three hold down bolts a turn or two, but don't overtighten! They are not meant to be very tight. Check Dometic documentation for specs and procedures.
Before it cracked, I did have occasional drops of water under the AC when the outside weather was rather humid and cool, and door/windows frequently open. Excess moisture was condensing on the cold inner surfaces of the AC unit.
If I were in your shoes, I'd watch it for further drips, especially when it rains, or humid weather w/ AC use. Mine would take more than an hour of use to start the dripping. If it drips, suspect strongly the condensate drain pan. This seems to crop up as a frequent problem. If its under warranty, confirm problem and take it in for repair.