Allowing users to add a "voice recording " that explains their problem ?
In my humble opinion it will be great thing if it happens .
This is a very bad idea for a number of reasons:
Video has similar problems. I'd rather read the transcripts of a video blog (such as http://www.eevblog.com/, which I don't follow largely because it's in a video) than watch the actual video.
If your project uses audio, and you need to play a sound clip to explain something (perhaps your microphone input or amplifier output is distorted in some way), I suggest using SoundCloud.
Other issues:
6- Is much harder to edit, and editing here is almost basic.
7- It's harder to relate the text to eventual (always welcome) pictures or schematics.
I think that multimedia files can be great, but if used as additional information, not replacing text.
8 - It encourages sloppy communication. I can just imagine "Um, this resistor thing, like, um, is connected to the third leg of the transistor, um, ...". No thanks. Forcing people to sit down and write up the relevant parts of the problem using words, diagrams, and pictures is a good thing. We get enough muddled questions as it is, let's not invite a whole new level of messiness.
9 - It's hard enough to follow the written word of some people who don't know english well. Having to understand words thru a thick accent will make it even harder.