Basically, all Harman Kardon amplifiers (including subwoofers) show power supply issues after a few years | The Wiert Corner - irregular stream of stuff
User manual Harman Kardon HKTS 200 (English - 6 pages)
Harman/Kardon Subwoofers... Burn Up Their Amplifiers... :( - YouTube
Basically, all Harman Kardon amplifiers (including subwoofers) show power supply issues after a few years | The Wiert Corner - irregular stream of stuff