Occasionally, upon starting up my FF400 I get a negative sample rate.

This happens regardless of start up, hot/cold, bus powered or ac adapter.

The sample rate in the Fireface Settings panel will show something like -1749302 (usually just random but always in the negatives)

Turning off, then back on always resolves this issue 100% of the time.

Latest driver and firmware

Macbook Pro 13" 2011 model