Hi @joshcowan
Try replacing the battery and check if that resolves the problem.
It seems like the battery is failing as it can't power the phone when the charger is disconnected and the charger can't run the phone and charge the battery at the same time, especially when the power requirements are high e.g. due to volume increase.
Here's a video that shows what to do.
Search online for HQ-70N battery to find battery suppliers that suit you best.
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