Could this be completely unrelated to the diving?
There is a condition known as suddden deafness that presents itself just as you describe.
Hearing Loss Assosiation of America describes it like this:
www.hearingloss.org
The slightly odd thing, is that there is actually a multi center study in Norway on the treatment of sudden deafness in hyperbaric chambers. (You might want to Google Translate this one, its in Norwegian)
helse-bergen.no
There is a condition known as suddden deafness that presents itself just as you describe.
Hearing Loss Assosiation of America describes it like this:
Sudden Deafness - Hearing Loss Association of America
Any sudden hearing loss, especially in one ear, should be treated as a medical emergency. Prompt medical attention by a primary physician, urgent care or ea ...
The slightly odd thing, is that there is actually a multi center study in Norway on the treatment of sudden deafness in hyperbaric chambers. (You might want to Google Translate this one, its in Norwegian)

SuDHO: Plutselig uforklarlig hørselstap og trykkammerbehandling
Formålet er å undersøke om tilleggsbehandling i trykkammer (hyperbar oksygenbehandling) gir bedre hørsel til pasienter som opplever plutselig uforklarlig hørseltap (sudden deafness) enn dagens standardbehandling gjør.