I have the same exact issue. It started showing up after 6K miles. It is more noticeable when the weather is hot. Haven’t figured out where it is coming from yet.
Not eBay. But it cost me $1000. It is not easy to change. The whole dash needs to come apart. Even the passenger airbag. But I did it anyways. Couldn’t wait anymore. If you need the contact to get the sync unit, DM me.