high pitched noise from the back on 2008 Ford Edge

I have a high pitched noise and have asked the dealer about it and was told this is related to the plastic fuel pump (if I understood) and there's nothing to be done. It's not always there but it's like having a dog whistle :) It seems to be more likely when it's chillier outside but not always there.

Asked by for the 2008 Ford Edge
Think there is a TSB on that, check with another dealer, talk to service mananger. Seems like it was something about the pump being to close to the bottom of the fuel tank, I may be wrong as I work on about anything that has wheels!
: what is a TSB?
The service tech. will know! Technical Service Bulletin.
Thank you! I really appreciate it.