回答“How do I fix no sound unless on speaker?”If I understand correctly: no sound from the earpiece speaker in calls? It's probably just a broken earpiece speaker, but try a factory reset before you attempt a repair.
回答“How do I change my gameboy advance volume control knob?”Hello, i think this video might help you: https://www.youtube.com/watch?v=GPwDf3Z1... .
回答“Can I change the battery of my OnePlus 3 to a OnePlus 3T battery?”Technically you can, but there is a very high possibility that it will only charge the battery to 3000mAh instead of 3400mAh. The batteries also have different voltages. (Watch JerryRigEverything’s video if you want to see it attempted: https://www.youtube.com/watch?v=n1sg2y8O...)