So this mystery is solved now, but I mainly want to document this so that others that are having similar issues can resolve the problem. If Mikrotik were to fix the underlying issue that would be amazing as well.
I have been having wierd network gremlins for the past 18 months. This manifested itself as frequently lost connections on Netflix and any other streaming services, but the most noticeable issue was that the Amazon Fire TVs would lose their connections to Amazon and lose it’s home screen. It would take about 20 or 30 seconds to come back and it did it quite frequently. Also, an XBOX couldn’t be connected to a wired switch as it couldnt connect to the internet after getting an IP from the DHCP server, but it worked just fine on wireless.
A few weeks ago I got a MacBook Pro and went through five different network adapters before I realized that it wasn’t the MacBook Pro. If I opened a terminal window and just did a simple ping (ping 8.8.8.8), I would get 20 to 30% packet loss - making it unusable. I received the packet loss just pinging the local Mikrotik IP as well (my gateway). Wireless worked fine with 0% packet loss. I swapped out cables to no avail. The really interesting thing is that I could pass through the adapter to a Windows VM and the packet loss went to 0% even though it was using the same adapter and CAT-6 cable, just running in a VM on the Mac.
The fix was to disable Fast Path in the settings of my WAN bridge (just change “Allow Fast Path” from yes to no). This immediately solved the wierd network issues plaguing my network. Mikrotik must be doing something different if the packets are coming from Windows/Linux/Mikrotik devices as those always worked without issue or packetloss. Their Fast Path algorithm just isn’t working correctly on certain devices. The reason wireless worked fine was that the wireless access point (also a Mikrotik) didn’t have the bug when connected to the Mikrotik router via CAT-6. I hope this helps other people!
P.S. My router is a RB4011iGS+ running 6.45.7