I'm having the same problem. Mine was a pre order too. Have you been able to find out the reason it is doing this? Mine's not been dropped or had liquid anywhere near it. Tyia
This is the 2nd S9 I have received from T mobile and the issue is I cannot hear the other party on the phone when I have it to my ear. I have called Samsung and they suggest that you go to Samsung.com/support to lodge a complaint. I would not recommend this phone don't purchase.
Just received my Samsung S9 over the weekend and I noticed that the call volume is very low. Also, when using the speaker the call goes in and out. The caller on the other end cannot hear you.
I just figured out that any liquid other than water can block the speaker on front screen.
Whilst cleaning the spearker with a damp cloth remembered my daughter accidentally dropping a few drops of milk on it a few days prior.
(thoughror clean with damp cloth, using water only and blow it dry)
This worked immediately for me!