Odd starting problem.

My 95 GM sometimes will not crank over. The instrument panel shows normal and all electrical funtions work fine. If you let the car sit for 10 min to 1 hr it usually will then start fine with no hesitations. You can hear the starter relay click when the key is turned forward. I had the battery and starter tested at Auto Zone and no problems were found as I has suspected the solenoid. The cables are good and I recently replaced the starter switch and the multifunction switch on the steering column. The transmission postion switch (nuetral start switch) was replaced a few months aog . I tried shifting thru gears like when I had probs with the sensor but it does not act the same as before and I think its a different problem. So I am guessing either the starter solenoid (can they act goofy like that and only work sometimes?) or perhaps one of the 2 starter relays. Any suggestions people? Thanks.

Jack
PS . The fuel pump is working fine and no check engine light comes on ever. I also tried replacing the computer module with no new results.