I've had it and was lucky enough to have it clear. Mine came on after a head impact which caused a bout of vertigo.
I was in hospital for four days as the vertigo left me unable to balance, and the Nystagmus made my vision feel like the vertical hold had gone on my eyesight.
Had various versions of the Epley manoeuvre performed on me, none of which helped, but it gradually subsided over a 2 week period.
I feel for you!