yeah, this happens for me when microwaving water in clean glass container. not pleasant, it goes off like a bomb in there. have mitigated it by putting a wood stick in the water, but later learned to just measure the water carefully and run the microwave only as long as needed.
theres no prescription here. but i go for "hot as i can get it by boiling off the water i can get to rest on it by then microwaving it". for me thats a good tradeoff in time, effort, and energy/water waste. no clue if it really helps the brewing that much but it stands to reason that the ceramic does steal some heat if its room temp. i do it right before. brewing. i also freeze my cup, so the resulting coffee winds up being perfect drinking temp right away after its done brewing xD
luv'n it