BackBeat PRO supports AAC and aptX, but OS X, by default, uses SBC. You need to download Hardware IO Tools for Xcode and use Bluetooth Explorer to enable those codecs.
The dscacheutil utility no longer works for OS X 10.10, the new one is
sudo discoveryutil udnsflushcaches
If your network connection (especially ethernet connection) stalling/freezing from time to time, try disabling the new MultiPath TCP (MPTCP).