No. Taking the effort to compose and type out a question is a basic first step to making it intelligible to the people from whom you want help. It's not failproof, but it can help clarify the issue in your own mind, which makes it more likely that others will understand your situation. People speaking without preparation lose track of what they are talking about, clear their throat and constantly use -- what are those things called -- oh, filler words, repeat things, mumble, and, just like this guy I ended up talking to on the bus the other day, will tend to ramble -- Christmas, he wouldn't shut up. Anyways... There's a far better chance of producing a top-quality question in written form, and we only want the best here.
Not to mention that, on SO at least, there's programming code involved in nearly every question and answer. Nobody wants to try to listen to you read your code out loud.
Finally, and maybe most importantly, voice recordings aren't searchable. The major impetus for these sites in the first place was to provide an archive of solutions to problems that will be findable and useful to people in the future.