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Replaced my LCD and digitizer (cracked). After reassembly, the received audio from the upper speaker was low and scratchy. I cleaned it, it got only a little better. Volume buttons don’t help. If I use headphones, bluetooth, I can hear fine, volume buttons work on those. If I turn on the call to the speakerphone, the volume is loud, but the other party stops hearing me. This is a different set of symptoms from other similar call audio problems on your site. I may have pulled the ribbon cable on the headphone jack. I assume the headphone jack needs replacing, but I wanted to see if I need something else because of the way the speakerphone option is acting. Thanks in advance, Commander Winc

If bluetooth is working on the phone, try an FM bluetooth transmitter to send to an empty car radio station directly. https://www.amazon.com/Nulaxy-Wireless-B