There's a sort-of fix, which is to CTRL+right click on the "reset midi and audio" button in the transport module. Sometimes you need to do it more than once. It resets all the faders to -inf, then brings them back up. Usually, this will wake the master fader up within a couple of goes.
Here's an interesting thing: this
never happened to me until this year. But if you read the forums, it's been happening since way back when the v700 came out, more or less. I've had mine for about four years, and it never happened for the first three of those.
Obscure issue, that's now very unlikely to get fixed. I've learned to live with it.