Can't speak for ab Equinox since I have never owned one, However, I had a similar problem with a 2013 Silverado and a Droid Maxx and the proble ended up being the phone book (contacts). GM customer assistance recommended I delete the pairing of the phone to the truck and the truck to the phone; then pair again and DENY access to the contact list. It worked from then on. Supposed to be a sofware upgrade in the future, but traded in for a 2015 Silverado and had no problem having it load the contacts, and the same with my 2016 GMC just purchased.
Give it a try; might be worth it.
