I had perfect hearing in that ear, smoked a high THC joint, and felt immediately congested. Congestion usually makes hearing diminish temporarily. But the next morning I still felt congested and then spent several weeks trying to yawn it away and get my ear to pop. Three weeks later I went to the doctor who diagnosed me with "sudden nerve deafness". Medically there is no known cause for sudden nerve deafness and the doctor had no idea either. But I did have a cold the weeks before, so who knows.

So yes, it could be this was all just a co-incidence but the precise timing of it all should give everyone pause. I did Google for similar stories and I did find one person with a similar story who was immediately dismissed because no one ever heard of such a thing. I do wonder how many people restrain from reporting such effects since the counter-argument is to provide casual evidence or get a doctor to confirm which is often not possible.

For sure there is a gross disparity in tolerance these days and you should avoid sharing hits of THC with anyone if your tolerance is low. They'll be fine, you on the other hand may have an experience you weren't expecting.