I own a iRiver ChromeX IMP-150 portable CD Player. In my car, I use a Philips PH62051 adapter kit which includes a CD to cassette adapter and a 12V DC to player power adapter (and both work fine).
At home however, every brand of 120V AC to player power adapter I have tried (including Philips) has not worked (the iRiver logo comes on briefly in the little window and then the player shuts off). I have read somewhere that only the iRiver AC power adapter will work with my player. But I would sure like to know why generic AC adapters, supplying the player’s required 4.5V DC and “positive” tip polarity, will not work. I am stumped !