4 out of my 5 jbl 125 sat home speakers have very very low sound, the speakers don't look blown

Judging by the simple fact that it has NO AC power cord or supply - NO.

http://audio-vintage.pl/product.php?id_product=198&id_lang=1

Subwoofers don't have tweeters and NO speaker makes spontaneous sounds unless it's mechanically breaking apart - then it dies and is silent.

I'd look for an electronic component that's blown. No one online can do that part for you.

Then you can say, 'oh, I see (something blown)' and spend time and money obtaining and replacing the low-hanging visible fruit only to find that the ROOT cause is not visible and you still have a problem.

OR let a hands-on tech take a look at it.

well it sounds like you know what the problem is already, the first thing you need to determine is if the fuze is blown, jbl's are expensive speakers and usually there is an internal and sometime an external fuze, sometimes the midrange and tweeters are fuzed sepeataly. I'm ont familiar with that particular model, but if it not a fuze then most likely you have overloaded the high end speakers and they may have blown out, the high freqency drivers and not cheap and if they are new and under warranty you might have a chance to get new tweeters/horns free but if it is your fault e.g. too much power going in, then you will have to pay for them. You can get replacemdent JBL or other good speakers at www.martinsoundproducts.com they are out of Cleveland Ohio and you can call them when you get their number off the website..

you want JBL Professional group if this involves the Eon product line.

1-800-852-5776

Or on the website

http://www.jblproservice.com/

Sound like the tweeter is blown, take to local jbl agent for service.

Try this Double click on the volume control icon in the system tray.Click on "options"--"Properties".Select Line-in and Mic.Mute them. I hope this solves your problem.

The JRX series have weak HF drivers, only rated for some 25 watts or so. Are you running in Bi-Amp or straight? Could be bad capacitors in the crossovers. Could also be clipping of your amp, a common cause of failure is using too small an amp and pushing it past it's clean operation limits. Speakers don't like square waves. Was the "Clipping" light flashing on the amp?

please use a different connectors and try if it works

You need two more speakers to get surround sound,ie> two front one center and two for surround,then you need a home cinema amp to run the speakers and decode the sound from your tv,sky,dvd etc,and the sub gives you your bass.

Hope this helps.

CABLE GUY.

Any speaker, if abused, can be blown. And if overdriven with dirty power at extreme levels it is not uncommon to burn out the voice coil. You might also want to check out the speaker surrounds. If they go, the speaker works but sounds lousy.

Localize the problem by hooking up two known good working speakers and see what happens. If they also do not work properly or sound like cr-p then the radio is at issue.