RNS-510 Noise - is it a gyroscope, inertial GPS?

[ACTR36Wagon]

Ok, the unit has a hard drive and a CD/DVD drive but I wonder if there is another noise. I wondered if one of the noises I hear from the RNS-510 is a gyroscope inside the unit. To quote an article on extra aids for GPS in cars:
"...a gyroscope and an accelerometer can be used for greater reliability, as GPS signal loss and/or multipath can occur due to urban canyons or tunnels"

[clip]

Ok, the unit has a hard drive and a CD/DVD drive but I wonder if there is another noise. I wondered if one of the noises I hear from the RNS-510 is a gyroscope inside the unit. To quote an article on extra aids for GPS in cars:
"...a gyroscope and an accelerometer can be used for greater reliability, as GPS signal loss and/or multipath can occur due to urban canyons or tunnels"

It's probably the cooling fan -I'm pretty sure they run one to keep the chip cool.

[G-rig]

Besides the HDD fan, I can hear a high pitched noise sometimes, but when you switch it off and on again it's gone.

Weird.