- 2017 MacBook Air running OS X 10.12.6.
- 1.8 GHz processor
- 8 GB memory
The wifi switches on and off every few seconds: one second on, three or four seconds off. (Note: I don't mean that it drops the wifi connection. The wifi shuts off, then turns back on.) This has been an intermittent problem for several days, but at first it was only an annoyance: the wifi would switch off briefly, then back on, and everything would be fine. Starting today, though, it's rendered the computer unusable. I have tried the following remedies:
Disk Utility first aid
Network Diagnostics (which froze)
Cycling the router
Trying to activate the wifi manually using
ifconfig, as described here.
The wifi connection on my phone is fine, so I'm inferring that the problem is not with the router.
Activity Monitor shows the
airportdprocess using 16%-25% of CPU
What is going on here, and how do I fix it?