There has not been any changes in TV that would affect TV tuner part since build 217. Somehow your Tuner is messed up.
Which channel were you trying to play when you first got the error message? I can think of one situation where that error would occur: when you play a channel number that is out side the range of valid channels - for instance playing channel 99 when you are using antenna instead of cable since over-the-air channels only range from 2 to 69 (at least in North America).
Try looking at the following values under "TV Settings" registry key:
"Country Code" - a DWORD value that should equal to 32 (decimal) or 0x20 (hex) for Belgium.
"Country Name" - a string value, should be Belgium.
"TV Tuner Input Type" - a DWORD value, should be 0 for cable, and 1 for antenna.
If the values are not correct, or do not exist, try change or create them.