High pitched whine with Xenons

[choC]

Do you have the driver assist in your car?

I do, but neither auto-hold or ACC were active at the time. This morning was the first time I had heard it in 4 days of driving (got the car on Friday) and I heard it on 2 separate trips today (out of 4 trips total).

It's a very high pitched whining/squealing noise and when I open the glovebox it becomes louder (either coming from that compartment or somewhere behind it). I could still hear it when the car was completely parked and lights switched off.

[choC]

Drove almost all day today, didn't hear the whining sound once.

If I open the glove compartment though I can hear a faint buzzing, but that could be the internal light globe.