That is very common problem with MacBook Pros & not much with MacBook Air, here is what you need to do, first Identify if it’s a right or left speaker that is having issue and next you can purchase the speaker from TEKDEP & remove the old speaker and replace with the replacement one, it should take under 15min and you will need P5 & T4 Screwdrivers to complete the task! Here is a link to both right and left Speaker! It’s should cost you under $30 to get the issue fixed! Checkout YouTube on how to remove and replace but it’s fairly easy!
Right Side :
15″ Apple MacBook Pro Retina A1398 – Right Speaker – 2012 . 2013 . 2014 . 2015 – TEKDEP
Left Side :
15″ Apple MacBook Pro Retina A1398 – Left Speaker – 2012 . 2013 . 2014 . 2015 – TEKDEP
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