I lost the installation manual on JHT525.

No. The jacks on the back of your tv are line level. That means no power. To get the power, you need a reciever. Red and white RCA wires will go from your tv's out and the other end to an input on your reciever, and your speaker will be wired to the speaker out jacks on your reciever.

i have the same problem..god damn it..

Disconnect everything, and turn it on. If it hums, it needs repair. Then try hooking up one cable at a time. If a connection hums, try another cable. If it hums no matter where you plug it in, try a 2-prong power plug adapter, or a ground-lift plug, as it's called. If nothing works, it may need a repair in its power supply. It would still turn on, but buzz no matter what you connect.

See if any electrolytic filter capacitors are blown (bulged at the top), badly soldered or if they have broken contact pins (legs), a loud hum in the audio suggests there is a non rectified (AC) voltage present which could be caused by a bad or badly connected filter capacitor.

There may as well be other reasons for the hum (a bad earth connection,a loosely plugged or badly soldered audio or internal connector, bad rectifier bridge or diodes, as the case may be, bad solder joints on any component, possibly other components that are faulty).

I just suggested some of more common possibilities.

Hope you can fix it.

regards

Triarcuate

Sounds like your connection is bad on the wiring to the Subwoofer. Try rewiring the connection with new wire.

I had this problem, too, and ended up throwing away the subwoofer. The reason in my case was the amplifier had a blown resistor. I could clearly see the burn marks and the broken resistor. I could have fixed it, but the subwoofer is 9 years old.
To find this, I unscrewed all of the bigger screws on the back except the two with the "ring" around the screw head. I then unscrewed all of the small screws. The amplifier/controller will come apart. Disconnect the speaker from the amp and then open the amplifier itself. In the "box" you will see a metal bracket, which was where the burnt resistor is.
Hope this helps.

I always type in the make and model on Google and most of the time I find an online manual.I've had some really oddball stuff but found manuals for em.

hi,i have 1000w 4 speekers but i have one amp.how do i connect to that?

Here is link to the manual:

http://www.remotecodelist.com/remotes/jensen/JR300C.pdf

If you have cables hooked up and have not installed them to the components when turned on the speaker will hum.
If your electrical outlet is not grounded properly you speaker will hum.
Personally I'd take it back and get a new one. if you just purchased it.
If this happens again try a grounded curcit first then go from there.