I'm having a strange problem..
 

I'm having a weird problem with the 330. At least once a day I'll have a few drops of water fall onto my foot. I'm wearing flip flops, so.. its noticeable. Could it be from the air conditioning or something?

I highly doubt that it's the AC. Did you ever had your windshield replaced? And is the car wet (outside body) when this happens?

I doubt it's the AC drain, but given how hot & humid it's been around here lately, perhaps it could just be condensation dripping off the outside of an AC line under your dash. Is the drip cold, hot, or cabin temperature?

It may not be the drain but condensation building up on the internal cabin pipes due to you rolling with either the top down and the AC on or just putting the top up and starting the AC and the pipes get colder than the interior cooling down as fast as the pipes.

I agree with Roc, condensation.

I second the humidity, when it gets super humid here sometimes my AC vent gets condensation, never on the X5 but on the 325i and LX470

I am having the same problem here in the last weekend, the passenger side got drifty. Think I switch from AC to vent air, then back to AC again, that's how moist got in and become watery...

The drip is always cold, and it happens more often when it's very humid.

I've had my windshield replaced three times, but the car isn't always wet on the outside when this happens.