I experience the ‘no audio’ problem as well on a XA2 with 4.2.
In the past a reboot worked, however, since the Verla 4.2.0.21 update even reboots don’t work anymore, I NEVER have audio on normal phone calls. Doing an audio call with whatsapp is no problem, but when I call someone by simcard, or receive a phone call, no audio in either direction.
After two years of using Sailfish I see no option than switch to Android I always managed to have a phone without Google or Apple, before I used Windows Phone for almost 10yrs…