Sonicwall QOS setup for VOIP phones

We have 3 offices a main and 2 remote offices. We have VOIP phones that apparently require QOS setup for the line quality to improve. The phone system vendor setup the QOS settings on the main office and 1st remote office on the Sonicwall TZ100s there and at the 1st remote office. We just added the 2nd remote office and I have the VPN setup to the main office on the remote offices Sonicwall TZ105 (sonicwall said the 105 is just the newer version of the 100) Anyway we need to set up QOS on the connection from the new remote office to the main on and the person at the phone system vendor who set that up is no longer there. I’m not that familiar with QOS setup and need some help. All I have is an email from them that says “The main office tz100 does have QoS mapping so I set that up to treat DSCP 46 (what the wave tags the packets with) at a higher CoS level for the switches to route. I was not able to set that up on the tz105 at new office because it didn’t have that option in the settings. They will want to be sure that they switches are set up to read the DSCP values in the packets so the the QoS tagging done by the wave actually gets expedited in the switch. The wave is set up correctly to tag all the packets for this higher value.

I don’t know what they mean by on the switches the Dlink switches at each location only have generic options for QOS where you can specifiy priority to certain ports. The way the network is setup the PC’s network connections run into the phones and then into the wall and switch port so that’s not going to help. I’d have to think if the TZ100 has some sort of QOS options then the 105 does as well but I cannot find it in either so I’m not sure how its setup to replicate it for the new office. Does anyone here know how I would make these changes on the new connection to the new office so the phone system will work properly