The (D) Button on Throttle is barely working.

Like the title says, the (D) button is barely registering on control panel when its being pressed. I have found a sweet spot, the top area on the black (guitar pick shaped) area around the LED button, and only at a strange angle. I tried using compressed air, thinking something may have been stuck, dust or something. Wondering if I should take it apart some how and take a look, no experience with electronics. Thanks for you time.