XT1096 Speaker volume quiet at start

I have a strange problem with my Moto X XT1096. At full volume, the phone rings as if I have turned on the 'Increasing ring' option although I haven't turned on any such feature. Because of this, the phone starts ringing at low volume which eventually gets loud after 2 seconds.

Is this normal? By the way I am using official 5.1 update.