20 Most Recent Onkyo HT-S780 System Questions & Answers

I fixed my subwoofer. The resistor at R16 (right next to the fuse) was the fried component. I removed it and replaced it with a 13K ohm 5 watt metal oxide resistor (from Mouser Electronics if not available locally). Works fine now. I got the solution and the circuit schematic from an audio hobbiest at diyAudio.com. This is, evidently, a fairly common problem.

Generally speaking, an amp protects itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'naked'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced and competent hands-on tech.

Check for loose speaker connections at the speaker as a root cause for intermittent shutdown.

How does speaker A work when you run the Test Tone or with a mutichannel input?

There are indicators for speaker A and B in the uper left of the display. If A is not illuminated, press the Speaker A button right below the Standby Button and see if it will illuminate. If not, try the SP A/B button on the remote.

i can help with that have you looked on the back of the tv at all the jacks you have look at the color of the jacks some are red and white those are for audio and the yellow is video you need a pair of cables that will conect from you dvd to your samsung that same color on both ends their RCA cables or analog cables

If the system uses a remote control, you may need to adjust the subwoofer out signal setting or turn on the sub in a menu, and on many systems, you can only access those settings via a remote control (you should check the onkyo user manual on how to do it).

Now, this is just one suggestion, it may work, but then again, it may not.

These could also be connection problems or some internal trouble in the onkyo sub signal output section or in the subwoofer input section, but hopefuly, it's just a "turn on" or "signal level" setting in a menu.

Good luck

3rq8 (triarcuate)

Your symptom sounds as though you may have to turn off any surround sound settings that you have selected in the other modes.

Most amplifiers use the surround portion of the amplifier to power the B channel speakers.

Since you have sound when using the radio portion, I would try turning off the surround mode. For example try turning the amplifier to just stereo and see if that gets the B channel speakers to work

I hope this information allows you to resolve this issue.
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maybe you have unfair inputs!? or your balance control is not working good... or you have defective parts! or maybe they change value like resistors and small capacitors, or u have leak driver transistors...

If your receiver has A and B channel speaker selectors you may want to toggle through the two and see if the sound comes back. That could easily have been pressed from the remote. If not try hooking up only one speaker at a time. If there is a short, or blown speaker the amp will usually shut its audio off so it doesn't damage anything internal. Hope this is helpful.

Code that I have for sky + is: 01175. There are several other codes for other versions of sky boxes if you think you may need them but that should be the one.

Samsung has a huge code list: 10017, 10037, 10047, 10054, 10056, 10060, 10090, 10092, 10093, 10154, 10156, 10178, 10226, 10702, 10766, 10814, 11060, 11235. Unfortunatly you'll just have to try them one at a time until you find one that works. Hope this helps.

Check to make sure that Speaker B is not pushed. It's on the front panel on the bottom left.

If you are using just component cables it's as simple as plugging them into the appropriate ports on the back. One nice feature of the HT-S780 system is the multiple digital audio ports and the ability to map them as you like.