You are right that much of it is not accessible. Luckily its not far away for the most popular of the components however.
I was able to introduce full skinning for the MP3 audio recorder last month, thanks to "The Learning Factory" in Brazil. That makes adding accessibility to the MP3 recorder relatively simple. The other recorders require similar work, but at least we have a pattern to go with.
The part that is not simple in all this for me, is exactly what the normal/desired behaviour of an screen reader, especially when it encounters an audio recorder. I was quite puzzled when I was testing with JAWS previously.