During some phone calls it just crackles,then ends the call and then freezes my whole phone up

[AC Question]

I'm from Ireland and I have a Motorola Moto G2 and I'm on the Vodafone network.A lot of the time during calls it just crackles and you can't hear anything anymore and it ends the call and freezes the phone and then you just have to restart it.Could someone please help me!

 

[STARGATE]

Hard to tell, but if I was you, I would save all my data from that phone into an external source and then do a factory reset to the phone.