Bluetooth on my iPhone 17 repeatedly disconnects and automatically reconnects during a single session. Started suddenly about one week ago after ~3 months of normal, issue-free use. Occurs specifically at the gym; not reproduced at home. Disconnect frequency worsens progressively within a session, begins around every 10 minutes, degrades to roughly every 3 minutes as the session continues. No overheating observed. Issue predates iOS 26.6.1 and persists after updating to it.
Troubleshooting completed with no effect: tested multiple headphone models/brands (including new units), reset network settings, confirmed fully updated to iOS 26.6.1, tested with Wi-Fi fully disabled using cellular data only, ruled out device overheating.
Device: iPhone 17, purchased from Apple Store ~3 months ago.