Thanks for the detailed report, @Dennis_Vanda_Laloge!
May I ask that you please provide a brief description of your current setup using this link as a guide.
Make sure to describe your network configuration/topology, including any networking hardware currently in use, so we can have a clear understanding of how your devices are communicating.
Are your DNS settings on ROCK any different than on your Mac? If you use Google DNS do you see any improvements?
Regards,
Dylan