New phone already having issues

So just before Xmas I spent large on a nice new Samsung Galaxy II S, top of the line Android smartphone. There were a couple of issues getting my number over to it, but that was resolved.

I received one call on it before Xmas and sound was a bit rough but I think that was the other end. Last night though I tried to make a couple of calls and couldn't hear the people on the other end at all.

This morning I've been running tests and digging around online. The phone speaker - "call speaker" and try disambiguating that from the "main speaker" in google searches.... - responds to diagnostics fine so it's not a hardware issue. It is an issue which seems to crop up quite commonly and is usually fixed by a software or firmware update but none are available.

Contemplating reset to factory settings ... I'm not going to try taking it back to the store until after New Year madness. Besides which, I'd be without a phone for however long it took them to sort it out.