Hi, Got an iPhone 6s and noticed that the ringtone is CONSIDERABLY lower when standing on a flat surface like a table. I normally get the ringtone/alert sound and vibration very clear otherwhise but as soon as I leave it on the table and get a text message, the sound is so much lower, close to mute sometimes. Any reason for that? I guess it's must be related to the motion processor that distinguishes the surface on which the phone is laying but still, it's so annoying! Any advice? thanks !