Do,
Normal sram stuff, but my only way arond this is.
Take wheel out
Pump lever, to push pistons out.
Re-place wheel or bleed spacer.
This helps as when everything is working well the lever extends the piston out then when you stop pulling the lever the piston relaxes back in the caliper and reduces the internal volume. Forcing the piston beyond the normal spacing, then relaxing back to give you the right gap for the rotor, gives you the volume inside the caliper to force the right amount of fluid in.
Ie you need to get more fluid in the caliper, with the pistons at full normal extension.
I have had all Avids and now run Trail and they only need bleeding to set this when replacing pads.