Thanks for the tip, I just did that and it caused no problems. I went back and checked each shield one by one to isolate the issue and the DNS problem seems to have resolved itself somehow.
Strange since 2 hours ago Avast One's shields were definatly causing the issue as I enabled/disabled them all to check. Maybe my ISP (Orange fr) fixed or whitelisted something since then.
Sorry for all the hullabaloo then.