Speedometer noise

Or at least that is where I think the chirping / squeaking is coming from on my 2005 4.0 Taco with 139K miles.

The noise came on rapidly and seems to kick in at 55 MPH and above.

Anyone know if this truck has a cable to the speedometer that may need some oiling or does it run digitally? I suspect a cable and a fun job to get to at that.

Any help or ideas appreciated.

 

The speedometer on 2nd gens is fully electronic (no cable) so I highly doublt its that.
It only does it above 55 mph?

 

Maybe a dash rattle?

 

OK, so here is the nutty part.

I lower the driver window to see if the noise can be heard from the outside. I raise the window and just like magic, no more noise. The only thing I can figure is that a leaf may have gotten between the fully raised window and its seat. Vibration can be fun.