I’ve got a very intermittent bird-like chirp that lasts for 1-2 seconds that sounds like it’s from the driver’s side dash. It’s not the A/C fan, not related to engine RPM or road speed. It sounds like a CPU heatsink fan that’s failing – a squeaky, chirpy burst for only a second or two.

Bently shows a fan on the back of the GPS radio, but I’ve got the basic Boost unit. Any other rotating things under the dash to look for?