Toilet burps and then flushes ok

Toilet started clogging frequently and required plunging after every other use. Used a toilet snake to clear possible obstruction. After using snake, when toilet is flushed it immediatly makes a pronounced burp and then seems to flush fine. Sometimes the burp is strong enough to splash a little water outside the bowl. I have a septic system. What could be causing this? Thanks for any possible solutions!
All other drains in house work fine.

The toilet snake you used likely was too small and just pushed the clog deeper into the drain. It's not plugged solid...yet, and there is enough capacity in the drain between the toilet and the clog to accomodate the flush so it's not running over...yet. You need to get a professional to properly auger the drain.

Sounds like there is still something in the toilet...

Toilet burps and flushes good

One of four toilets in new 3 story house, consistently burps and then flushes good. If flushed within about 45 seconds of the last flush, it does not burp. It has completely refilled by then. Wait any longer and it burps. My burp defined: this is an air bubble in the bowl smaller than a tennis ball. My plumber believes it is the toilet itself, not any type of drain issue. Any thoughts?

In the bottom of the bowl there may be a hole about 1/2" in dia. This is called the siphon jet. Is the bubble coming out of the siphon jet?

If it is clean the holes inside the bowl up under the rim using a piece of coat hanger wire and make sure that the bowl refill tube is in place on the top of the flush valve overflow tube. Also make sure that it sprays water down the overflow tube when the tank is refilling.

If the bowl water level is not refilling high enough or, the trapway has gotten craked and the water level leaks down this bubbleing out of the siphon jet can occur.