Video suddenly lost

[David Hoyt]

> error: gst_waveform_sink_prepare: waveOutOpen failed error=>A device ID
has been used that is out of range for your system.

This sounds like an issue with your audio output device. I would open up
device manager and take a look at the device configuration for conflicts,
missing audio drivers, etc. If you find an issue, I'd suggest you write a
patch (against master) to detect and then more gracefully deal with that
scenario.

That said, I'd pose a question to the gst devs -- is there an environmental
sanity check done on the system before pipelines begin to roll? I know it
might difficult (nigh impossible) to do an exhaustive check, but a quick,
straight forward one would make sense. Just a thought...