/dev/dsp got more sensitive about writes?

Hi all,

I've updated from r302211 (June 26) to r306427 (yesterday), and the
behavior of audio/sox (in its play(1) alias) seems to have changed.  I
used to be able to suspend play(1) for an arbitrary period of time and
have the output continue when it was foregrounded again.

Now, it seems that I can only suspend it for 4-5 seconds and retain
playback; for longer sleeps, I get

[1]+  Stopped                 play 01\ Mary\ Hynes.wav
[root_at_glossolalia ...]# sleep 5; fg
play 01\ Mary\ Hynes.wav
play FAIL sox: `/dev/dsp' error writing output file: Invalid argument
Done.


Wrapping play(1) in truss seems to change things, though; in that case, I
can sleep for at least two minutes and still recover playback.  So that
makes it a bit hard to see what's going on.

I will note that I did not upgrade ports/packages after the base upgrade,
so the sox binary in use is potentially somewhat stale.

Does that ring any bells for anyone?

-Ben