Bought an iPhone X for next to nothing. The screen had been replaced by someone else. The phone function is hampered by no working video, no speaker audio, no audio on calls. No volume control on side. Volume control- on screen- has a mind of its own. However, when hooked to Bluetooth... all those issues disappear. Logic board? Software? Dirty connection? Just replace the screen again? Give it to my mother for her birthday- because she’d not know the difference? Thanks in advance!