A little while ago I wanted to enable Audio on my Hyper-V virtual machine. Below, I will share the tip that allows you to enable remote audio, dual monitor support, printers, and other options on a Hyper-V RDP session.
Step One: Open Hyper-V Manager Console.
Step Two: Start your Virtual Machine
Step Three: When your Virtual Machine is running, right-click on the VM and select Edit Session Settings.
You should then see a box similar to the one below. On the dialog box, you can select which resolution you will connect to your VM and whether or not to use all your monitors. Click Show Options.
Once you click show options you will get this dialog box. Click Local Resources. (Also make sure to select Save Settings for Future Connections)
Once you click the Local Resources tab, you will get the following box. 
Under Local Resources, you can specify your remote audio settings as well as whether to use your printers and clipboard, etc. Just make sure to save your settings.
I hope this helps! If it did please consider following me on Twitter and check out my YouTube Channel for more tips.
This was posted by techspeeder.
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You idiot,
Please explain how this will enable multiple monitors………..
Your dumb article pops up every time and causes time wastage
Hello noby, this article solves your problem ! Thanks.
To add more monitors, just exactly follow the steps, at resource, click available monitors (if displayed), enable PnP since almost all monitors are simple plug n play devices, this means no need extra driver or config for each PnP. Also tick recognize device I plugged later.
Only “Settings…” when I right-click on VM, NO “EDIT Session Settings” option, :
Same problem “Edit Session Settings” option is missing for Ubuntu 20.04 vm on Hyper-V manager v 10.0.19041.1