Totally my fault for not investigating potential issues first, but I purchased this housing for an upgraded portable Time Machine drive used exclusively with my mid-2015 MacBook Air. (The drive was originally used in a USB2 external enclosure for Time Machine backups with an original white mid-2007 MacBook, so USB2 was all that was required.)
The Good News: This 2.5" external drive housing is high quality, and nice looking, and it works. Time Machine data backups are now faster than the same 1TB 7200rpm HGST Travelstar drive in the old USB2 portable enclosure.
But as I discovered almost immediately, a USB3 signal MAY interfere with WiFi signals (and vice-versa), especially IF the USB3 device is located near the WiFi and Bluetooth antennas.
On the mid-2015 MacBook Air both antennas are apparently located low on the screen in the back near the screen hinge. Because of the short USB3 cable that ships with this enclosure, I originally placed the drive enclosure BEHIND the MacBook Air on the desktop and routed the cable directly BEHIND the computer.
That's a no-no! Because suddenly, my WiFi was no longer reliable. As in, long periods of 0% throughput. Even after rebooting, clearing caches, resetting SMC and PRAM/NVRAM, and updating to the latest version of macOS, High Sierra 10.13.2 (and now 10.13.3)
The enclosed short USB 3 cable comes equipped with two large magnets near the ends to minimize RF interference. Unfortunately, in my setup, there is still enough interference between the USB3 signal and the Wifi signal to bring the WiFi connection to a crawl, or a complete halt. I tried both 2.4Ghz and 5Ghz WiFi connections and re-orienting both the MacBook Air and the router. 5Ghz was a bit better than 2.4Ghz but still not even close to reliable.
What to do? Current Solution: I purchased a longer .9 meter USB3 cable (from the OWC Garage Sale - I will review the cable when I complete this write-up) so it should be among my list of Reviewed Products soon.
With the longer cable, I relocated the USB3 drive enclosure as far away from the MacBook Air as physically possible, on a nightstand about .8 meters away from the computer, stretching the new cable straight out from the MacBook Air USB port to it's full length of about 1 meter, with no cable near the hinge area. Even though this longer cable lacks any magnets to reduce RF, the interference problem has completely disappeared, and both USB3 and Wifi are coexisting peacefully and reliably again.
