Now that a 4.0.x kernel is in testing, I tried this again. $ uname -a Linux iset 4.0.0-2-amd64 #1 SMP Debian 4.0.8-1 (2015-07-11) x86_64 GNU/Linux The bitrate is still incorrect. It appears to be constant at whatever the first sampled value was since the system last booted. The link quality and signal level metrics are correctly set and fluctuate as you use the system.