iMP-550 and replacement AC adapter

[marcoaet]

Hello

I lost the AC adapter for my iMP-550 during a recent trip. Since I live in South America, ordering a replacement is complicated, so I bought a universal adapter at an electronics store. Nominally, the specs are exactly the same as the original one (4.5V 1.2A DC).

I recharged the batteries from about half full, and I got the impression that the player got hotter. I unplugged, and checked the batteries, and they hade 4 lines (full). I know that the battery indicator isn't accurate but I didn't like the thought of the adapter sending power to the already charged batteries.

I never payed attention to the heating up when I had the original adapter. My question is, is this heating up normal? Could the original iRiver adapter be the one managing the charging, or does the player do that?

Thanks.