I will only add that due to yawning, the pressure is equalized and after an instant interference with hearing, hearing improves. This is one of the functions of yawning. Here with a picture:
Why does the hearing in the ears change, and sometimes the sensitivity of high and low frequencies changes when yawning or sipping?
The fact is that when yawning, the canal opens, which leads from the oral cavity to the eardrum and through it, in fact, getting into the inner ear creates pressure on the membrane, thereby temporarily impairing hearing.