Hey,
It sounds like your battery is degrading after five years. Here’s what you can do:
# ***Replace the Battery***: This is likely the issue. Buy a high-quality replacement from a reputable source like iFixit or well-reviewed sellers on Amazon.
# ***Check Connections***: Since you’ve opened the headphones before, make sure all cables and connections inside are secure.
# ***Safety***: Avoid cheap batteries to prevent safety risks.
If you’re not comfortable doing this yourself, consider a professional repair service.
Good luck!