I think that all the optimizations were mostly done in the media player and not to pulseaudio.
For instance, the FM radio player still stutters horribly and sometimes just stops playing completely after a few pauses in the sound. But media player almost doesn't stutter anymore.

Also can someone tell me why CPU usage is so high during a phone call? Is it due to pulseaudio or the phone app itself when it is communicating?

I still think that any optimization to the pulseaudio package are welcome, even on PR1.3. Unless it's simply impossible without the risk of damaging the speakers...