Some MPEG players (Microsoft Windows Media Player, for instance)
cannot play back MPEG live streams from a URL. So, AVBroadcaster
may include the "Content-length" HTTP header in the MPEG stream.
Simply add key HTTPContentLength to section [AVBroadcaster] in
settings.ini (located in the same folder with DVBCore.dll).
Valid values are from 1 to 4294967295.
The default is the 0 ("Content-length" is not included in HTTP
header).
ex.
[AVBroadcaster]
HTTPContentLength=52428800 ; 50 MB

If a player can play a live MPEG stream from a URL, such header
is not needed, if not - player play specified amount of bytes
with 100% precaching.