Network Lock on Debian host - Windows guest no network

[George123 4]

Hi all,
I'm running Debian Buster and have a Windows 10 guest set up in qemu via virt-manager.
I have Eddie and Hummingbird installed on the host, and have this same issue with both - namely that when Network Lock is enabled and I'm connected to Air on the host, the Windows 10 guest has no network connection.
When Eddie/Hummingbird are not running, guest works fine.
When I use Eddie to connect without Network Lock, the Windows 10 guest connects fine and has the Air exit IP address, as expected.
So, something about the way Network Lock works is preventing the Windows guest from being able to use the Debian host's network.
I'm using the default NAT network that virt-manager sets up.
I'm also using AppArmor - I know qemu has its profiles set and enforced, don't know if this is relevant.
Any help much appreciated!
Thanks.