Headphone jack PCB connection
You can ignore pins 4 and 5; just leave them unconnected.

However, be aware that as you plug into this jack, pretty much every possible combination of connections will be made before it is completely seated. This includes connecting the positive supply to the negative load or vice-versa, shorting the power supplies to ground, connecting one or both power supplies to their loads with no ground connection, etc.

Make sure your circuits &mdash; on both sides of this connection &mdash; are robust enough to handle this.