I've got an RPi3B+ running LE 9.0.1 without experiencing this issue.
When the problem occurs again can you.
Please provide a full debug log.How to post a log (wiki)1. Enable debugging in Settings>System Settings>Logging2. Restart Kodi3. Replicate the problem4. Generate a log URL (do not post/upload logs to the forum) use "Settings > LibreELEC > System > Paste system logs" or run "pastekodi" over SSH, then post the URL link