Help fixing a pair of speakers?

Hey everyone :)

Well, a few years back a German exchange student stayed at my place, and she left this pair of speakers. They used to sound really nice, considering their small size. They were forgotten for maybe 2 years, and when I tried using them again I get this:
-A loud "pop" when I turn them on
-When on, there is a very low hum, very electrical sounding
-When I connect something to them, the volume is very low, and rises barely even if I crank the volume knob all the way up, all I get is a lot of crackling if I do this.

Here are some pictures.
http://img.photobucket.com/albums/v1...Bocinas004.jpg

http://img.photobucket.com/albums/v1...Bocinas010.jpg

http://img.photobucket.com/albums/v1...Bocinas007.jpg

http://img.photobucket.com/albums/v1...Bocinas006.jpg

http://img.photobucket.com/albums/v1...Bocinas009.jpg

It reads:
TS5725 A-B 230V/12VX2 1.5A
Thermal Fuse 130ºC
BC

I live in Mexico, we use 120v/60hz if I'm not mistaken. I suppose I need to change it so it works correctly with 120V? However, remember they used to work perfectly. Any help/suggestions greatly appreciated :)

What are you plugging them into?

In other words, what is the source: computer, MP3 player, receiver, radio, CD Player?

They have RCA connectors in the back, I have connected them to a PS2 and a Creative Zen (This usually has low output for speakers, but still, the volume is way too low)

Offhand, there's a disparity between what your electrical system provides and what these speakers SAY they need to operate. Did she have some sort of adapter for these?

Remember, you were there when they were last used, not us.

The only adapter used is the physical adapter, she didn't use any type of electrical converter. I also used them a few times on the PS2, and they sounded great, not using any type of electrical converters. Then, I didn't use them for maybe 1 or 2 years, and when I did use them again, they had this problem.

The sources you use wouldn't cause the problems you describe.

Since you say you've used them successfully without any adapters or problems since she left, I'd say that the amp subsequently died. I'd say it's time to move on to another set of 'puter speakers.

So it seems! A pity, they sounded really well (For an enthusiast).