Once again I had encountered problem watching IPTV at home. After spending a lot of time again I finally found the solution. Again the problem laid in LAN interface conflicting the virtual NIC interface created by VirtualBox. IPTV is served using IGMP protocol and UDP. TV channel addresses look like udp://@238.0.0.28:1234. It happened that my LAN addressing space didn't overlap the address space used in the virtual NIC, but as the virtual NIC had lower metric it was used by default to send IGMP group membership packets. So, to resolve the problem it is just required to change virtual NIC default metric to a higher value. This can be done on Windows 7 in this way: go in to your network adapter properties page for the virtual NIC, from there click on Internet Protocol Version 4 and go to Properties, from there click Advanced. Change the metric to 800 or higher. That's all.
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