static in left earbud while on call & 2 more issues

My left earbud makes a loud static noise only while calling using only the left one or when using both. This noise is heard both by me and the other person in the call, however when using the right earbud only there is no issue.

Second more common issue both earbuds are unusable in noise cancellation mode or transparency mode, in both modes they make static noise but at a lower pitch and higher volume it seems.

Third and last: both earbuds have been making a crackling noise lately when listening to music or movies etc. This only happens when music or sounds are in the bass range and when volume is higher than 75% more or less.

Thank you to any helpful wise iFixer! I’d love to attempt a repair so any tipps gladly appreciated^-^