Hearing Spanish in background during Thursday Night Football

We've been dealing with the same issue since upgrading to Contour and moving have a mile across the street. Pre-season football on channel 7 would start in English and then switch to Spanish and reverted back twice, finally settling on Spanish. I actually kept the recorded game and played it for the Cox representative on the phone so he could hear it switch between languages. He had never encountered the glitch. I told him I cannot be the only guy in Orange County that has this issue. It did it again on the national NBC Sunday Night Football game last night. Channels 2 and 11 don't do it, and neither has any cable broadcast. I have to go in to SAP and check the box for Spanish and the game then reverts to English. For the record, the Sunday night games on channel 4 actually have no audio until I check the Spanish box and then it goes to English. Channel 7 actually broadcasts in Spanish until corrected.        

I made sure we had English selected as our language and we did. Just for kicks, I switched it to Spanish and it began broadcasting only English

From that I'll guess you're streaming with a browser or using the Contour app and not watching the TV broadcast.  When I watch the NFL game on watchtv.cox.com (NBC) with Chrome, I hear the same thing you're hearing.  There is English audio with Spanish in the background when SAP is OFF, but audio is clear English when SAP is ON.  There is no issue with TV audio on the Contour box.