It happens to me sometimes too, 2 things help me so far - turning off BT in the phone before making the reconnect, or starting playback some while after they both reconnect. Disabling Smart Connect event related to the audio device seems to do the trick for some of them, on the headset it was enough to add an action "connect bluetooth audio" in the SC, but you never know which way works for the specific device (it happens with all BT audio devices- headphones, headsets, etc).
I am sure it is some kind of bug. Current Android version, at least afaik, doesn't have full support yet for the hardware BT installed on the phone (and it's Google's fault, not Sony's) and the A2DP protocol itself doesn't support buffering (so it is vulnerable to low signal level and will chop the audio for sure in such case) but still it all worked fine on my old XS, so I suppose we have to wait for some update about it, this is a common problem. Perhaps someone already have some better solution than above (just wait, they'll join), but I know for sure that SUS'ing the phone was just a waste of time, so it certainly is something wrong with the phone.
