Not sure where to go, but...problems with audio on my stereo*

So some time ago, my stereo started to have troubles. The problem is that I love it too much to replace and I have no idea what to do or where to turn to and I hope a light can be shone in the darkness that has befallen my system, a little hi-fi unit that will do anything outside of Bluetooth.

Playback on all formats is perfectly fine - there is no problem reading anything. Radio, CD, USB, SD and auxiliary inputs work like new.

The audio, however...

After a period of perfect audio, the volume suddenly drops, there is serious distortion and the L and R speakers seem to go off balance.
On top of this, if a USB is plugged in, the audio is distorted even further and somehow reacts to the LED on the flash drive even if I switch the system to play another format. Playing a CD is fine, but the audio plays the motor as it whirrs the tray open, to then interchange between L and R. The problem affects the headphone audio as well.

The weird thing is that most of these problems seem to cease if the volume is turned all the way up, then gradually back down.

I'm willing to fix whatever the issue if if it isn't digital, though I'm not willing to crack her open to fiddle with her until I am certain what I'm doing.

 

You should fill in all of your audio gear in your profile. It will help other members better understand what the issue may be.

 

What d'you got ? Apart from a dirty volume potentiomenter there's no way to tell if you don't provide make(s) and model(s). Are you maybe listening through a mini-chain or boombox ?

 

Sorry, I'm new to this. It's a Teac MCD51MU, a little mini HiFi system that could sit on a coffee table. Has FM radio, USB, SD card and axillary inputs along with its CD player.
The issues started when I left the system on mute and forgot about it for a couple hours. Funny thing was the system never actually completely muted; it would reduce the volume below its minimum un-muted volume capacity to a barely audible murmur.

That's about as much detail as I can think of at the moment- buggered after a day tiling a kitchen. Hope it helps

 

First things first. Google "Deoxit" and give it a try. Good luck.

 

Released 6 years ago. Price: $99. Maybe time to move on.

 

Mute can be either a volume reduction of, say, 20db or a flat zero depending on the ear. First step is always cleaning things with Deoxit as mentioned, but I am wondering if something in the power supply has gone FUBAR.

 

If anything needs to be repaired, it'll cost more than what this system is worth.

Buy another one and move on. My 2 cents.

 

Unfortunately, the problem lies with that TEAC player due to its poor build and parts quality and non-existent QC.

 

Yes; unfortunately these things are not made to last more than 5 years. My wife loves mini-chains but all she's had have started to develop problems after 5 years; first thing to quit were cassette playback, then most switches go crazy, and lastly the CD player starts refusing to read some discs.

Replace or get something :

a) cheaper like a U$ 100 boombox; they can sound real good (I own a QFX active speaker with FM and mp player and it rocks) . Of course I have it for kitchen and patio duties.

or

b) more expensive but more durable and rewarding, like a separate receiver/CD player/speakers, like most of us on this forum do.

 

I have to agree with Strat Mangler, time to move on.

 

Could it be (a) piece(s) of cheese fallen through the case and shorting something out? .

 

So I have to agree with others who say to just replace it. That's going to be less than pro repair costs. If you want to try to fix it yourself, and you accept that if you cannot that you will have to replace it, then there is really nothing lost in trying to fix it. You will need to unplug the unit from the wall so that there is no power to it. You will need tools that fit properly the screws and any other fasteners to remove and replace them. You will need patience and memory to take your time to take it all apart without breaking anything and to put it all back together exactly as it was, also without breaking anything. That may take some time. The problem is likely either a ground point that has failed by oxidation or heat build-up, perhaps the mute switch itself, or a resistor, or a part of the circuit or board in the mute circuit that attaches to the resistor or ground point. Either cleaning or soldering may solve it, probably both, if it isn't too badly damaged. No idea where these components lie other than the actual mute switch, but probably very near that or remotely via a wire or circuit trace that leads from the mute switch. If you can't find those components or repair them, it's time to start saving another $100.
-Bill