I've just recovered this very interesting thread from the archive... I'd like to share with you my experience and specially WG774 tell u about my theory... that seems pretty similar to yours...
I've been flying since 2003 and this year first time in comercial ops / pressurized. I've never had problems with my ears before, even being allergic to many things. After a period very high emotional stress... i've begun to suffer from blocked ears both during climb and descent but worse during the last 5000ft of the approach... due to the bigger pressure difference, i guess.
Every ENT doctor talks about otitis media, rhinitis, sinus problem etc... but my experience is that medicines for that doesn't solve the problem. I'm in the same situation as you... but one day I started thinking about the possible relationship between tension and blocked ears. There's a lot of stuff on the internet about that but not very clear though.
One morning, when sympthoms were better (as you say), while still on the bed I started thinking about a problem I had which created me stress.. one minute later my ear was blocked. On my last days off i went to the beach... no problem with the ears... i was relaxed, but the day before starting flying my ears went blocked again.
I'm convinced there's a direct relationship between my blocked ears and tension / stress... and also because after a back and neck massage session I feel my ears unblocked sometimes inmediatelly.
Any comments on that? WG774 can you update us on your current status? I'm very interested and supporting 100% your theory about muscular relationship.
Cheers!