how many thread process used by rygel

[Soho Soho123 <soho123 2012 gmail com>]

Dears,

per observation from Rygel verification,
when I start rygel by "rygel -g 5&", there are 2 threads run on my
target platform.
when I play a MP3 from W7 media player, then there are 6 threads run
on my target platform.
when I stop playing MP3 from W7 media player, then there 2 threads run
on my target platform.

Does anyone have idea about there 4 threads are started when rygel
playing audio ?
which gstreamer element start thread ?

and another question,
I can see the main function of rygel,
rygel_main_run(), the function will call g_main_loop_run() to start loop.
why there are 2 threads stated in main function?

Thanks!

Best Regards,
Soho