short press number 4 :When 7 14 Volume adjustment VOL into RPT 13 1 playing audio video,optional song,BT can dial.Long press A.V.P Music/Movie/Photo Switching short press number 2 :When playing audio video,optional 2 song,BT can dial. 2 15 3 short press number 8 :When 5 8 4 16 5 17 6 18 9 short press number 5 :When playing audio video,optional playing audio video,optional song,BT can dial.Long press song,BT can dial.