What would cause a continuous buzzing from the passenger side door speaker?

I have the same issue with my 2011 Ford Explorer XLT. The passenger side door speaker makes a buzzing noise, regardless of whether the radio is on or not. It has been getting worse lately. Also, going over bumps in the road can make the noise disappear, come back, or change intensity. It sounds to me like a wire is grounded or frayed, because as the engine RPMs change, the frequency of the noise also changes (the speaker noise goes to a higher pitch as the vehicle accelerates, and vice-verse.

I have the same problem. Did you ever find an answer?

not a repair but more of a question: mine seems to happen when I put the window down and up a couple of times. Then when it does start humming and I put the window up and down the noise gets worse. But if I shut the car off for about an half hour the noise goes away. So I think it is something in the power window motor that is back feeding into the speakers.

I have the exact same problem. Has anyone figured it out?

My 2011 Explorer is experiencing the exact same problem. The Ford dealer replaced the radio and right front passenger speaker last December to try and remedy but the noise returned shortly thereafter. The noise is intermittent and will go on and off after hitting bumps in the road. The car is presently back at the dealer for further diagnosis. I did seem to notice a correlation of the noise happening more frequently when there was precipitation. The dealer was going to test that theory as well. Based upon the feedback in this forum, the problem does appear to be systemic. I hope Ford addresses this problem for the consumer.

Did anyone figure out a solution? My 2012 is having the exact same problem and my sanity is at stake

I knows it's years later, but I seem to have it figured out. There's another forum I found where a man found that the ground wire from the amp is bolted down ontop of paint which is a no no. He removed the back passenger side paneling to find the amp, scraped off the paint under the grounding wire and reattached. I'm working on this now.