A lot of Canadian football fans who tuned into the American NFL game between the Chicago Bears and New Orleans Saints in HD last weekend were disappointed to find the coverage had been switched to another source once the game began.

Canadians who had tuned to Fox Sports on various cable and satellite outlets available in Canada were forced to watch HD carriage from Global "that many Digital Home readers say was deeply flawed and virtually unwatchable," according to Digital Home Canada.

The NFL pre-game show reportedly aired in its entirety on Fox and was a flawless 720p broadcast. But after cable and satellite operators replaced the Fox signal with the feed from Global, fans began to complain that the video had become plagued with motion artifacts and a picture that at times appeared out of focus. "The problems were especially acute during plays when the background was changing quickly and players were in full motion," the Web site said.

"We [also] experienced prolonged sound drop outs and, after commercials, it was typically 10 to 15 seconds before a very grainy standard definition image was replaced by the HD image," Digital Home said.

The tech site confirmed the source of the problem by hooking up an antenna and viewing the Fox broadcast from Buffalo, N.Y. It found no problems with the Fox broadcast. Digital Home said it then contacted Global Television about the problems, but had not yet received a response.