Seat belt light sometimes flashes/clicks
 

Every now and again, the yellow seatbelt indicator on the console flashes and makes a ticking sound as though someone isnt wearing a seatbelt. It starts up then stops. Any ideas?

I had this problem - though often my horn would sound and the lights would pop up at the same time.

I solved the problem by jumping the two wires under the driver seat that go to the seat belt clip. A closed circuit here actually signals that the seat belt is not clipped. (Even though the RX-7 has a seat belt light and wiring to detect that a seat belt is on or not, the bulb in not actually activated in normal operation to the best of my knowledge.)

Another possibility is a low battery, which has been known to make the alarm system (controlled by CPU #2, which also has a connection the seat belt clip) to behave erratically.

In any case, my fix may not work for you but it is easy to try. You could also test your battery to see if it is near the end of its life.