I have MacBook Pro 13" mid 2012 with 16GB RAM and 256GB SSD, Mojave 10.14.1. my Magic Trackpad 1 and AirPods get slow when CPU is too busy, especially when cpu percentage is above 70%. My USB-wired keyboard and mouse seamlessly work even if it is too busy. I wanted to try Apple Hardware Test for more details, but it says the error code DEC400 so I can't do that. I have an appointment at Genius Bar to check for my Airport card this Friday. I am worried they refused to fix it just because my mac is too slow.
EDIT: When executing Java programs from IntelliJ IDEA, sometimes Bluetooth devices get slow but sometimes work well. Maybe some other factors makes them slow. I had the same problem when I worked on Sierra.
What I found out from Bluetooth Explorer
- Mac drops the connection to the AirPods from some reasons. logs says the reason is 0x08. I think Google and Apple official user guide are both silent on what the reason code indicate. Some other factors somehow affect my AirPods, as well as a busy CPU.
- When the CPU is too busy, the Throughput graph goes down dramatically.