My machine is making a high-pitched sound!
The issue can most likely be fixed by oiling the moving parts of the machine. Focus on the square, white bearings at the top and bottom of the machine. Add a couple of drops of general sewing machine oil on both sides of the bearing and turn the machine on. Do this several times until the machine runs smoothly.
Oil at least monthly, but more based on use. You can't over oil it so don't be shy.
This might also cause the machine to "beep."