Porn Audio Starts Playing During BBC Broadcast, Network Apologizes

The BBC's broadcast of an important soccer match got super sexual ... audio from what sounds like a pornographic movie started playing ... and now the network's apologizing.

It all happened during the buildup to Tuesday's FA Cup match between Wolves and Liverpool, when BBC broadcaster Gary Lineker was suddenly interrupted by the sound of a woman having an orgasm.

Gary was barely able to contain his laughter as he told the audience, "I wasn't expecting that noise," before asking a reporter at the game a couple questions.

In the moment, Gary openly wondered about the source of the porno audio, saying ... "Somebody's sending something on someone's phone, I think. I don't know whether you heard it at home."

Yes, yes we did, Gary ... we all heard it loud and clear.

During the match, Gary tweeted a photo of a cell phone with some adhesives and captioned the post, "Well, we found this taped to the back of the set. As sabotage goes it was quite amusing."

The BBC is already apologizing "to any viewers offended during the live coverage of the football this evening" ... and a network spokesperson says BBC is investigating.