RX7Zero

Been having issues with my digital speedometer in my 92 coupe the last few days. When first started in the morning and on the drive to work, neither the dash or window speedos work. On subsiquent trips later in the day however, they start to work find again. Fuses are good, dunno wat else to check with these symptoms? Anyone have any thoughts?

NismoSpD20

speed sensor and or the gear that is on the sensor
I had the same proplem with my hatch so i the speed sensor and gear,didnt work.. so swapped my cluster with the digital one and hud works fine