I have a similiar issue. I installed to Toto Drake toilets. One of them does the same thing and the other does not. I had the same problem with my prior toilet in the same bathroom.
The plumber who installed them has been out to my house twice. We verified that the bowl was level and all water level wereset to Toto specs. Even had the Toto Tech on the phone. Since I had the same issue with my other toilet the consensus is there is not defect in the toilet.
The toilet are back to back with each other seperated by a wall.
The plumber does not believe it is a vent pipe clog, ( this could be your issue)
as the other toilet works fine and threre are no other plumbing problems in the house.
He does not know if it is being caused because the toilets are adjacent to each other.
Bottom line there is no solution per my plumber for the issue. He suggests I live with it!This could become an issue for you as low flush toilets require all
the water in the bowl to achieve the proper flush.
Maybe someone has an answer to this situation