Animal Archive introduced the Familiar Spell feat, which lets you imbue a spell into your familiar. One of the limitations on it is:
A familiar spell uses up a spell slot 3 levels higher than the spell's actual level. Your familiar can store a number of spell levels (including this modifier) equal to your caster level, but no spell's adjusted level can exceed half your caster level.
Normally, this means you can't use this feat until you're 8th level, at which point you can store a 1st level Familiar Spell in your familiar (8/2 = 1+3).
Animal Archive also introduced the Familiar Metamagic Rod which lets you cast "up to three spells per day that affect his familiar as though using the Familiar Spell feat."
So the question is, what is the spell's adjusted level while the familiar is holding it? Does the rod bypass the "no spell's adjusted level" check? That would let even a 2nd level caster grant a spell to their familiar. Or does the spell's adjusted level include the increase, even though the rod accounted for it instead of a higher-level spell slot?
Effectively, what is the "adjusted spell level" for a spell cast with a metamagic rod? The rods specifically say they don't adjust the spell slot of the spell, but nothing about its level, beyond what the standard metamagic rules say.
If it doesn't change the slot, I see nothing that changes the level.