Before taping it, load it up and take it for some hikes...
Good advice. Load it up to, or close to, the max weight you expect to carry. Things that are quiet with a lightly loaded pack start making noise when you put some stress on them. For my Eberlestock J107 and X1, it was the XL hip belts at the point that the belts rubbed over the front end of the hip pad. Generous application of candle wax and/or bees wax (Lyman bullet lube) to the surfaces took the squeak away.
