I upgraded to 1.6.1 over the weekend and since then, my Xbox360 as a Media Center Extender using Windows Media Center for Live TV stopped working properly.
Since the upgrade, the Xbox360 will wirelessly make a connection to the Windows Media Center PC, but the Live TV functionality does not work properly.
I can verify that the PC running sees the connection from the Xbox360 and the attempt to watch Live TV acquires a tuner connection properly, but there is no Video/Audio on the Live TV stream.
Rebooting the router solves the problem temporarily, but it quickly returns the next time I try to use the Live TV functionality via the Xbox.
I have downgraded back to 1.6.0 for the time being and the problem has subsided.
My setup:
WNDR3700v1
PC running Windows 7 Ultimate 64-bit
Silicon Dust Prime TV Tuner + TWC Tuning Adapter