Hello raverlof,
Thank you for reporting the issue.
Could you please help us with investigation by providing some data?
Please enable debug logging (Menu > Settings > General > Troubleshooting > Enable debug logging)
Reproduce the issue (when DNS is not working).
Create a support package (
https://support.avast.com/en-eu/article/Submit-support-file) and post the ID here. If the support package does not work for you, could you please zip whole log folder located in C:\ProgramData\AVAST Software\Avast\log and send it directly to me?
Thank you very much,
HK