I have a unique situation, and have picked the brains of quite a few people, to no avail.

I have a Rheem Criterion gas furnace. Here is what happens:

Draft inducer initiates
Igniter (electric) lights up
Gas is fed through a minute later
All 4 burners light up simultaneously (for the most part)
All 4 burners start "pulsing" simultaneously (about 2 times per second)

When we first moved into the house the burners were smooth, but after a couple years this "pulsing" thing started. When I first noticed it, it would start slowly at first (about 1 pulse every 2 seconds) then smooth out. Then the pulsing would increase in frequency. Now it doesn't even smooth out, just a consistent 2 times per second. The furnace heats really well, cycles on and off accordingly. I'm just concerned about this "pulsing" thing. Any ideas?

SelfHelp7

Sounds like a defective pressure regulator.
What kind of gas do you have natural or LP?

It sounds like hvac probably told you the answer but one thing that you could do if you would like is to call your gas provider and have them run a pressure test on their lines, it could be too high and your regulator is just trying to compensate for it.