Just upgraded to OSX 10.12.3. It was a clean install on a 2014 Retina MBP with a 2.8ghz i7, 16GB, 1TB PCIe. While the machine is working perfectly the file transfer speeds over wireless are incredibly slow. We're talking over 30mins to transfer 2GB. Both my other machines (2006 MBP and 2017 Dell XPS15) seem to manage this in under two minutes to the same destinations on my network. General web browsing, youtube and netflix all work fine. Any ideas?