TurnerGuy, its your middle ear that the Eustachian tube (ET)ventilates via its opening at the back of the throat. Try using an Otovent ballon to inflate your ET as this safer than pinch and blow, a Valsalva manoeuver,as this could lead to a perforated eardrum.
Otovent ballon
UrbanHiker, this could be involuntary spasms of your tensor tympani muscle, one of the smallest muscle in the body. This pulls on the bones in your middle ear, a defense against loud sounds, causing the eardrum to move, the crackle wooshing noise you hear.