If you are using a refurbished display, check for dirt in the earpiece speaker cutout.

If you have poor quality or low sound after changing the display, use a cotton bud and isopropyl alcohol to clean the earpiece cutout.

One more addition I had to make after undertaking this repair.

I had noted that after swapping the display the earpiece was very quiet. I thought that I had missed a gasket, misaligned the earpiece speaker or not plugged in the leads correctly.

Nope. Much simpler than that. CLEAN THE EAR PIECE CUTOUT! *Eeeewwww* After putting up with this for about 4 weeks, I happened to get out the Cotton Buds. A quick wipe revealed someone elses EAR GUNK was clogging up the ear piece cutout !

Disgusted, I got out the Isopropyl and cleaned it (carefully) about 10 times, the audio is now crystal clear.

@ifixit - Please ensure your “Refurbished displays” have a clean earhole. It was pretty gross that it was clogged to the point that I could not HEAR!

Completed the Repair with the more Expensive alternative - the OLED display.

The guide is very comprehensive and covered all the points including looking out for bits left behind!

- I noticed a tiny piece of conductive foam on the old display which i moved to the new one.

The OLED display is top quality, but a little darker due to losing the “True Tone” no doubt.

The Adhesive kit is very good, but separating the two films was a little difficult and messed up the alignment slightly, however I managed to recover!