I have 3 older (T12) Lithonia lighting fixtures that all behave the same way. When wired to the light circuit in each case the inner two bulbs light up the outer two bulbs do not. If just the inner two bulbs are wired to the circuit, they light as expected. If just the outer two bulbs are wired to the circuit, they do not light up. Is this a wiring problem, a specific ballast problem or are they just being pissy?
Thanks

You need to replace the tombstones... (the bulb sockets).. likely corrosion... they are cheap anyway.

Could be the ballast in each fixture for the outboard lamps are all defective.

Try one fixture and swap the known operating ballast for the inboard lamps to the outboard lamps.

This will test the ballast and the lampholders.