We have a fairly nice (~ $600 new) Onkyo home theater receiver that’s about seven years old.
The front left channel has started popping/crackling. The closest description I can think of is that it sounds like someone is playing a very dusty old-timey record (remember those?).
The amount of crackling varies over time, but there is no pattern (it doens’t need to warm up or anything, and it can be minimal for stretches in the middle of a program).
I switched cables and speakers and it stays with the channel. That is, I connected a different speaker/wire combination that worked fine on a different channel, but was noisy on that channel.
Does this problem sound like a typical receiver glitch that’s usually fixable? Is it a case of way too many things that could be wrong and it’s anybody’s guess?
I had warranty service done on it years ago (unrelated issue), and that repair shop wants $165 (+ $60 in back-and-forth shipping + Onkyo-specific parts cost) to repair it. So I’d be spending at least ~$225 plus the chance that it’ll need more than basic parts.
I’m hoping to get some insight as to what’s wrong before I spend the first $30 to ship it there. Maybe even an easier fix than shipping it off?
You could try some electronics grade contact cleaner and some lint free cloth or cotton swabs and clean the contacts on the speaker wire and receiver (Do this with the power off…)
If you have banana plugs or other connectors verify they are securely fastened to the wire.
If not, examine the wire for signs of oxidation (looks dull/corroded instead of shiny).
Take a flashlight and have a look into the top of the AVR to see if there is a lot of dust in there , that can have some odd effects occasionally.
Since the crackle follows the channel and not the speaker, that is about all you can do unless you’re willing to crack open your AVR and I really don’t recommend that unless you know what you’re doing.
Dirty switch is also my guess. But there can be several possible culprits. So exercising anything that can produce a change in what’s coming out the speakers could temporarily help. Once you find out which one it is, then a quality (like DeOxit) contact cleaner could be used judiciously.
But my experience is that once this starts happening, it will come back all too soon and you either live with the device or without it.
If it’s unrelated to dirty contacts in balance or volume pots - very typical, it sounds a lot like failing power supply capacitors. These are electrolytic types, the “cans” you see under the hood. It’s important not to operate the unit if this is the case. If you’re handy with a soldering iron the repairs are not expensive or difficult.
It’s very unlikely that it’s worth spending over $200 to repair a 7-year-old receiver. You could probably go on Craigslist and buy a nice 2-3 year old one for that money, or maybe a newer refurbished one online. Receivers are like computers, a new low-end one will probably have more advanced features than yours, although it might not have quite as much amplifier power.
Wrangled it off the shelf and did a bit more testing. Brought out two different speakers and connected them with simple wire; left channel popped and crackled. Was using a computer as a source (even swapped out the PC I was using, one that is known to work well in a different room), and with the volume turned down it still crackled. Plugged in headphones; crackled through the left ear. Changing the volume on the unit did not make a difference.
Haven’t opened it up yet to look around. Aren’t I supposed to be very careful with the guts of a powered amplifier (or am I thinking of old television sets)? Will leaving it unplugged for a day or so drain the capacitors so it’ll be safe?
Also didn’t think to try the sub-room switch (i.e. the ‘B’ of the A/B speakers). Damn. Could it make a difference?
The receiver is an Onkyo SR707. I don’t know what the used $200 equivalent or better would be.
Trying the “B” speaker connectors is a good idea. Sometimes the problem is with the speaker on/off switches. (The stereo above the computer I’m using has this problem, on both.:()
As to cap charge: Not really a worry for something like this. No big charge on these caps and they self-discharge very quickly. Notice how the lights dim out when you turn it off.
I work on very fussy A/D conversion units.
Cleaning often solves a lot of problems. The very fine pitch of the leads can cause a variety of problems when crud builds up. Particularly in the pre amplifier areas.
Get some canned compressed air. Good quality electronics cleaner. Blow it out first. Try and do it with the unit upside down as well. Apply the cleaner and blow it out while it is still wet. This stuff can dry real fast. Careful not to get it in your eyes or breath it. Flammable too. After a thorough clean, let it dry for a good long time. The cleaner will seep under components and sit there for quite a while. Leave overnight near a heat vent is good.
Cleaning solves a lot of our problems. But then our problems are seldom audible. Just show up as 0.0001 off specifications.
Is the audio being supplied theough HDMI? Some Onkyo receivers develop problems with their HDMI inputs over time, and it can manifest as crackling audio, video that won’t sync until the receiver is warmed up (or not at all), and other issues.
If you aren’t sure, you can eliminate that as a possible problem by trying another audio source.
In any event, unless it’s something simple like a dirty potentiometer it’s not worth repairing.
With Onkyo the equivalent would be any model that starts with 7, although you could probably live with a newer 6-series, depending on what sort of features you’re looking for.
I haven’t done anything of consequence. I took the cover off to look around inside but didn’t spray any air or cleaner in there (it was pretty dust-free and no sign of swollen anything).
I brought it downstairs to the basement workout area and was going to use it’s “B” speaker channel for a regular pair of speakers. For whatever reason, I connected the speakers to the “A”/main room terminals to give it another chance or something.
And there was no problem. It ran for seven or eight hours over the holiday break without making a single pop or crackle. Nothing at all.
I’m bumping this because my plan was to replace it today (so-called “cyber-Monday”) with something on sale. But now what?
To repeat what I’d done while it was still making noise:
[ul]
[li]Different speaker wires (both a different one from the 5.1 system and cheap extra wire I had on hand)[/li][li]Different speakers (both a diferent one from its 5.1 system and a pair of small speakers used in a different room)[/li][li]Different inputs (two different HDMI inputs and my work laptop’s headphone output via a 3mm-to-RCA cable) [/li][li]Different sources (a HTPC and a cable box through the HDMI and my laptop)[/li][li]Different outputs (crackles and pops were heard through the speaker and through headphones)[/li][/ul]
It didn’t seem related to temperature/warming up, because when it was upstairs it started happening within a few minutes of turning it on (but it was somewhat intermittent), and it ran downstairs for a few hours at a time.
I don’t want to spend money on a non-holiday purchase, but if I need to replace it this is the time to do it. Could it be as simple as a lose connection that’s unrelated to the speaker terminal (since it’s coming out the headphone jack too)?
A local repair place had suggested sending it into an Onkyo repair place because they’d have cheaper access to parts/boards. Do I go back to him and ask for him to fiddle with circuits (I figure it’s at least $80 in shipping back-and-forth to Onkyo, so he’d have at least that to start with.
Or is it likely to go some time soon and I’m better off taking advantage of a sale now rather than in February when itgoes completely?
If I bring it back upstairs, could following Kedikat’s advice of spraying air and good quality cleaner in there (brand?) end up doing more harm than good (if it’s a loose connection) or likely to make it last longer? (Also, if so how do I recognize the “fine pitch of the leads” and “dirty potentiometer” mentioned above?)
Hope you took the opportunity to pick up something to replace that 707. It’s not worth spending anything on, but one thing you can try for free that might do nothing useful at all is a factory reset:
I had a 707 that died last year with the well known HDMI board capacitor failure. For whatever reason, mine wasn’t covered by the recall, so I replaced it with a Denon AVR-X3200.
The air won’t cause any harm and it sounds like it might have been a connection problem. Clean electronics are happy electronics. We use LPS No-Flash on our radar equipment but any electronics grade, plastic safe cleaner should suffice.
It’s remotely possible you might be having interference on your power, so if it shows up again at the previous location that could be your culprit, especially if you have anything with a motor, like a fan, or a microwave on the same circuit. Both can generate a fair bit of noise. Troubleshooting is fun, isn’t it?
