QThanks for bringing to light current problems with El Capitan and Bluetooth. My problems started when I upgraded my 2010 iMac to El Capitan, and I’m concerned that when I replace it later this year, I won’t only have problems with wireless peripherals, but with Bluetooth networking too. Should I insist on seeing it working before I buy?
AThere’s no evidence that current Mac models have underlying problems in their Bluetooth hardware, which consists of well proven chips and, as you’ve found, can work properly for both peripherals and networking in older versions of OS X.
These issues are far more likely the result of kernel or driver bugs. In normal use, the latest iMacs seem fairly reliable, and dropouts are infrequent, making their use with wireless peripherals largely trouble-free. Networking may be a little more prone to problems, but those should only be an occasional irritant.
There’s no way for users to alleviate or fix these issues: they await revisions to the drivers in El Capitan or, if not there, in Sierra. Always keep a wired mouse and keyboard to hand to help with entering Apple Hardware Test or Diagnostics at startup when needed. Apple supplies USB cables with its latest wireless devices for charging them as wired USB devices, although their purpose isn’t to work around Bluetooth problems like this.
Hopefully Bluetooth problems will be fixed, both with updates to El Capitan and in the macOS Sierra upgrade.