QoS help

I am trying to set up QoS to improve the quality of my VOIP service. I have a 25/2.5 connection and have set the following limits;

Max Outbound: 1500
Max Inbound: 15000

I am only using two classes right now (one for the VOIP ATA, one for everything else):

Highest: From 192.168.1.10 (the address of my VOIP ATA).

I have the default set to High and the following for my outbound settings:

Highest 90%-100%
High: 10%-100%

I am stumped as to what to set for my inbound settings... Can I set No...

QoS help