STR-DB870 problem - centre speaker cuts in and out.....all speakers "pop" at random times, when they all "pop" the centre either turns on - or - off and stays that way way indefinetely, all terminals checked and rechecked, speaker works fine, tested on other output, it is the output from the amp to the centre that appears to be causing the issue, how do I fix this???? help please

Try replacing the center speaker with one of the left or right speaker and run it for sometime ( do not connect the center speaker to any other channel ). If the system does not cut off the center speaker connection this way indicates a short in your center speaker.
But with the L/R speaker if the system still stops working you have a hardware problem and will need professional help to fix. 5.1 amps are complicated and difficult to access even for an experienced technician.

If the power of the Receiver is ON, press Power to turn OFF the power. Then, hold down the MODE + button and press the Power button together.
S.F Intialize appears in the display and all sound fields are reset at once.

Disconnect all speakers, then test power. if it cuts off, your receiver needs serviced. If it stays on, Check all your speaker wires for shorts and connections at speakers. If they seem ok, re-install one speaker wire at a time and test power. once you find the speaker that's causing the problem, replace the wire and connect a different speaker (that you know works) and test again. If it cuts out, the problem is in the receiver and needs serviced. If it plays, put the original speaker on the new wire and test again, If it cuts out, it's a bad speaker or internal crossover depending on the model. Unless you are very proficient with a meter, this is the easiest way to check your connections. If you still have questions, post a comment and I'll help some more Hope this helps

Bad solder joint. Dirty contacts (servisol switch cleaner) or a broken switch. I would have thought!

just repaired my se 501 poor solder conections on blue rleays by speaker jacks,also blown center speaker seems there are 2 in it one blew and so did cpacitor running now just hooked up one in center speaker sonds great also stay at 8 ohms setting

HI...
You have a "ground loop" problem.
It's related to the AC wiring in your place.
I dont know if you have a Walmart or Home Depot type store near you but,if you do, go to one and ask for a AC circuit tester. Should be a 3 prong unit with LEDs. Plug one into where you have the stereo and see what it reads.
You might have lost a ground connection in the AC outlet

Hi,
your problem is a bad solder connection of the relay linked to the lautspeaker sockets. I had the same problem and googled for the solution. Since I resoldered the pins everything is fine. That problem is well known and happens to a lot of Sony receivers.

I can send you a link with a detailed how-to-do solution with pictures, however it's written in german language. But you can use some online translators.

Here is the link: http://www.bmw-syndikat.de/bmwsyndikatforum/topic.asp?TOPIC_ID=28280&FORUM_ID=20&CAT_ID=9&Forum_Title=Geplaudere&Topic_Title=Problem+Sony+STR-DE445

Ralf (from Germany)

Maybe, it worked for me. my rear speakers workt ramdomly, often not. so i re solder the relay for the rear speakers, now it works fine everytime, a hole movie and some random on and offs, it can't do any harme to try=)

Hello,
Please download user manual of STR-DB870 from Sony Support.

Hi. I have a SONY STRDB930 receiver and the rear speakers started cutting in and out, with a clicking sound. Eventually, the centre channel followed suit. I turned the receiver over and removed the slotted panel on the bottom. This allows you to access the circuit board, where you will find the solder joints belonging to some blue relays that you can see down on the bottom if you shine a torch in from the top. Check these, as I found 4 of them appeared to have broken. The solder blobs should appear shiny, without any dark ring around the pin. If they look dodgy, re solder them. I did this, and it appears to have fixed the problem, at least for now. These relays are what is clicking, and they turn the speakers on and off. If the voltage supply to the coil of the relay is interupted, by a faulty solder joint, for example, the relay will cut out.I hope my solution is not too late for you, I have only just gone online recently.