Why will phone calls on my Apple Watch Ultra not send audio to EarPods or Powerbeats Pro?

When using my AppleWatch Ultra (1) over LTE (not carrying my phone with me) to make or receive a phone call (both direct calls and FaceTime audio) using ear pods, calls initially work fine until I have listened to music through the watch - from that point all subsequent calls will not send the audio through the headphones. I’ve tried this on both EarPods Pro and Beats Pro. Doesn’t matter if the music is currently streaming or paused. The call does connect for both parties, just no audio. If I switch the audio mid-call to the watch speaker, it works fine. I’ve updated both phone and watch to the latest as of April 26. Anyone else experiencing this?

[Re-Titled by Moderator]