Apple tv 3 gen + imac 2007 2.8ghz with itunes mavericks + airport extreme 2gb

Hello :

When I 'm looking at the appletv 3 generation with the last firmware update , HD MP4 movies in 1080 with high bitrate (no greater than 20,000 ) + AC3 5.1, size 12-18 gb movies from my itunes imac to share at home, and movies stored on an external drive via USB 2.0. The router I use is a airport extreme 2 gb latest model of Apple .

The start seeing great uncut and stoppages , but in most films or almost every am not able to see the whole finish , because I suffer from stoppages in the middle of the movie . sometimes the white bar going forward but still stops at some point in the movie, and not other times I see the white bar in front and then stops as if itunes does not send the movie to appletv3 .

I'm sick of looking at all possible configurations , I have opened ports , disabled IPv6 on ethernet and wifi. Connect Wifi 5 GHz Wi-Fi also probe a 2 GHz and has been the same. I have WPA encryption password with this with this router I can not change to leave open . Off screen protectors and imac energy saver set to never rest hard drives.

The internet works fine on the appletv content with others without cuts.

I can no longer look and more so I commented here , if anyone can help me with some settings more or any suggestions you can think of .

A greeting.