iOS client bug - white screen after swapping apps

Prerequisites

Volumio Information

Volumio Version: 2.915, and also 2.917
Hardware: Raspberry Pi 3b+
DAC: external USB DAC, HRT Music Streamer II
Client: iPhone XR with iOS 15 and iOS 15.0.1.

Debug Log

Steps to Reproduce

This started happening when I upgraded my iPhone XR to iOS 15, and still happens with iOS 15.0.1.

  1. Run Volumio UI app on iPhone
  2. Switch away to another application
  3. When switching back to Volumio client after a minute or so, or more, there’s nothing but a white screen.
  4. At this point, it’s necessary to exit the app using a swipe-up (the usual means for exiting an app)
  5. Rerun Volumio app on iPhone
  6. Volumio app appears OK.

Additional Information