Recurring "rescan already queued" message

[Dmitry S. Kasterin]

> I had the same issue on my laptop with an eSATA port.  I disabled the
> eSATA port and that made the messages go away.  According to mav@ these
> were harmless, but annoying.

I've found the topic here:
http://forums.pcbsd.org/showthread.php?t=16055

The problem has been solved by setting "hint.ata.1.pm_level" to "1".
Now the messages are gone and I'm pretty happy.

My thanks to Sean and Alexander.