raoultrifan
Headphoneus Supremus
Just take it into a different home, perhaps in a different neighbourhood too and see if it does the same. What are the odds to have the same DC voltage on a different home few km/miles away from your place? If it will do the same, then maybe the transformer has an issue or the internal power regulators are drawing too much power out of the transformer; if so, then something inside your H20 might be the culprit. You may also use a cheap 3-pole-plug power reading device to check the current/power drawn by the H20 with volume to the min. and with the volume to normal listening levels too.