Sony KDL50W805B sound issues

[Heba]

Hello Guys,

I got a major problem with the sound on my Sony and I don´t know how to solve as.
When I play certain videos on my TV the sound doesn´t work properly. It´s a sratch noise every second with a pause every second:

sratch pause sratch pause ...... and so on.
The files are .avi files with:
Bitrate: 192
Chanels: 2
Rate: 48 kHz

When I convert them to .mkv with:
Bitrate: 64
Chanels: 2
Rate: 48 kHz

everything is ok.
It´s the same effect when I stream it with UMS, WMP or directly with an usb stick.

If I use "mencoder" in the transcode folder it works even with the .avi O.o

Is there any option to solve the problem that I don´t need to go through the #transcode folder?

Thanks!