I think we're on the same page here. Usually qualia are brought out as a proof that there is some kind of ineffable quality that can't be replicated by machines

I think we're on the same page here. Usually qualia are brought out as a proof that there is some kind of ineffable quality that can't be replicated by machines, but can only be experienced first-hand by truly conscious beings. I see now that that was not your argument, and you're interested in an answer to what produces the feeling of qualia.