Question about Sony STR-DE945 Receiver

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Mono only mode problem

Hi all, This problem has started to get progressivly worse over time. When I first turn it on, it clicks and I have normal sound (Front L/R and Center). It may or may not click again immediately and only play from the left speaker. It used to only do this every once in awhile, no it almost always immediately goes into "left speaker only" mode after that first click you hear when you turn it on... This morning, it clicked and no sound came out of the left speaker...sounds like the thing is going bad.... Any ideas? I tried disconnecting speakers and plugging things in one at a time, but the behavior is the same. Thanks Mike

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Re: Mono only mode problem

Oh, well in my case Tony5 is wrong, relays are blue and cover not coming up, as suggested JDSpin I took out the circuit board which is actually not that easy as he says (be patiend!!!) and just re-solder all of relays joints. If they are look just fine, You might want to take a magnifying lens to take a closer look on the joints. Good Luck Thanks JDSpin

Posted on Jan 13, 2007

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Re: Mono only mode problem

Mike I have the same receiver and until recently had the exact same problem. It would click on start up and as it warmed up it got progressively worse, sound from the speakers was sometimes terrible and very muffled. However, if you tapped the top it would click again and them work again for a while. Anyway, I finally got around to taking the thing apart and found the problem was caused by dry solder joints to the relays attached to the main circuit board. To fix it, take the cover off and you will see 4 blue relays in a row OSA-SS-212DM3. You will then have to take out the circuit board which is actually easier than it looks. Once you have it out just re-solder the dry joints. Alternatively take it to a TV repair shop and they should be able to do it for you relatively inexpensively. I hope this helps.

Posted on Nov 04, 2006

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Re: Mono only mode problem

I had a similar problem, but all speakers would go off (not just one channel). I would hear a click and functionality would be temporarily restored when I over-twisted the A/B Switch, tapped the shelf and/or pressed on different parts of the case. After several experiments, I found the solder joints were broken for the two sets of header pins for the board-to-board connectors on the Display PCB. These connectors link to the Muting and Power PCBs located on the left and right sides respectively. Because the through holes are not plated and there is mechanical interaction (board-to-board flex connection and in the case of the interface with the Power PCB--constant button twisting and pressing), these solder connections are especially prone to failure. To confirm this problem, you will need to remove the front panel assembly (after you have removed the cover, remove eight screws around front plastic, unplug two flex cables and remove one end of ground strap). The back of the 5 pin header connecting the Display PCB to the Power PCB can be found on the upper right side of the Display board (marked with a "5" in a square); you may be able to see fractures in the solder connections or feel the pins wiggle; otherwise, you can easily confirm this problem with a continuity meter; make sure that you are testing the continuity/connection between the pin and the board itself while moving the pins/connection. The pins for the Muting PCB connector are on the far left side of the Display board (by "DISPLAY" marking). Resoldering the header pens should restore happiness for a few more years of successful performance.

Posted on Sep 03, 2006

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Re: Mono only mode problem

Toni5 gave the correct reasons for the problem you are facing. But, instead of usinga file to clkean the relay's contacts, i normally use a fine grain emery sheet or Sand paper. Cut up a small patch maybe an inch square, and use these.

Posted on Jul 17, 2006

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Re: Mono only mode problem

It sounds as if you have dirty or sicky relays in the speaker outputs. These relays are there so protect the amplifier's circuitry should there be a problem with your speaker system. If the amp detects a fault it won't switch the relay to allow the speaker to be used. Obviously you don't have a speaker problem but because the relays are dirty or sticking audio isn't being allowed through. By tapping the unit it's activating the relays as it should. If you wish to find the culprits, WITH THE POWER PLUG PULLED OUT. look for small clear plastic boxes on the motherboard, Maybe 1 1/2 inches tall and and inch square. With a bit of pulling and luck the clear plastic top should pop off and leave the innards on display. Gently insert a very fine file between the contact points and give them a few rubs. Do this to all the contacts and put the plastic top back on. Try the unit out and see if one channel works. If it's all OK do the rest in the same way. It's these relays which you hear clicking by the way. If they're dirty they'll still click but not do their job. bmw

Posted on Jul 16, 2006

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SOURCE: Sound cuts off

he's partially right... I have fixed 3 shorts on my de845. 2 have been caused by cracked solder joints. they were speaker cutout problems...yours most likely is the center channel relay on the main board. take the thing apart. you need to get to the back of the main board and re-flo those solder joints. get your geeky pc buddy and do it together(buy him a sixer). its really not that hard...just a bunch of screws. disconnect everything from the main board including the front plate. be careful with the ribbon cable...mine is hurting at this point. not meant to be removed so many times. put it in straight. my leads bent, but was able to straighten them. there are 5 relays together, one for each channel. they are white cubes and prb a little smaller than the tip of your finger. its the 4 leads on each of these that you want to take a soldering iron to . i'm not sure which ones the center channel so do them all in that area. it may be hard for you to tell which leads they are so just go overboard and at least get everything in the vacinity. i did all component leads because who's to say another's not ready to go bad. you've gone this far. touch the heated up tip to all the leads at the very end of the barb. you can reflow the solder without actually touching it. the metal lead will get hot enough. hold it until the solder liquifies, then let it cool. do this on a flat surface. my other fix once was a re-seating at the speaker switch a,b,a+b on the front plate. there are 2 boards plugged together there. i bent the leads slightly so they seated in more tightly. if your left or right front goes out, sometimes thats an easy fix...try b if you're using a, or the opposite. don't forget the speaker cables. if you're using both zones then you prb already figured out you need to re-flo! test and cross your fingers. good luck.

Posted on Jul 27, 2007

SOURCE: Receiver making alot of clicking noises.

I Have a son STR DE 845 and the speakers make a popping sound when it is in DTS mode what is the problem.


Posted on Jan 28, 2008

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SOURCE: Center speaker

mine is doing the same thing, you can hear a click sound and the channel will die. I think it is a relay or a shunt that trips when something goes wrong with that amp. I dont think it is worth repairing as there are some nice receivers out there for cheap. Maybe just a cold solder joint somewhere? Anyone know where and Ill dive in and resolder and post the results.

Posted on Feb 24, 2008

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