It looks like the Speedlink driver may have to be installed separately using Windows 7 compatibility mode. You may also have better luck with 3.10 if you can use it.
Go to GN ReSound Support Website
Then click on Documents. Under documents there is one called “Speedlink & Windows 8/10 compatability with legacy software”. It may walk you through a fix for your issue.
Back on the main link, there is a Releases, Updates, Patches button. It has the new version of Aventa. The Drivers button has the latest Speedlink drivers.
This is all a guess on my part though. I’m using 3.10 on Windows 7 with a Airlink 2.