Downloaded recordings have audio but no video?

We have a server set up to automatically download our class recordings every night. It has worked fine since we set in up last July.

However, the last few days it has been delivering FLV files with only audio, no video.

Here are some diagnostics:

1. The recordings play fine when streaming or downloading, video is there on the Adobe recording server.

2. We can see the video playing as it downloads on our local recording server (we have a laptop RDP into the server at all times, so that the server generates the video for the recording).

3. The downloaded FLV files are markedly smaller and clearly can only hold audio, not video.

Thus far, only one class has complained, but I expect a wave of complaints and a backlog of classes needing to be re-recorded.

Is there some setting or bad Plug-In version that could be causing this?