High beams not staying on
 

My 90 Accord has developed an annoying problem.
Driving home at night I use my high-beams when driving through the rural
roads, of course shutting them off when another car is approaching. Lately,
after turning on and off the high beams a few times, the high-beams won't
stay on when the switch is pulled and relased. The switch will click, the
blue light on the dash lights up, as well as the high-beams, but as soon as
I relase the switch, they fail to stay on.
Is this a bad combination switch or maybe a faulty high-beam relay?
Also, after the car has been parked for a bit, the problem is gone for a
while.
Thanks.