XA2 Single Flashed 4.5.0.19 here.
I don’t have these problems. Audio went away once/twice, I believe, but long time ago.
My XA2 is not slow (I’m not demanding much at the same time either)
GPS works nicely now. (seems to be very device-depending and XA2 hardware is sensible. Dunno for the XA2 plus though).
I am using Pure Maps evert day, which is really a great app IMO.
IIRC, some providers reach a limit of demands, sometimes, and don’t display maps (correct me if I’m wrong) but generally, it works well. OSM Scout can assure you to have maps all the time as one can download them in advance and use them offline.
You can even have HERE routing, taking traffic in account and HERE maps which are nice and detailed. See this thread for more infos: https://forum.sailfishos.org/t/pure-maps-native-map-app/6494/165
I’d also recommend to reflash your device.
Whish you good success with it!