fun sound...


ant

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a friend knocked my beloved console off my desk today... only about a two foot drop... nothing seems to be wrong... EXCEPT:


it now makes this incredibly irritating, low-volume high-pitch whine whenever it is on. it sounds rather like a square wave...


it's not very loud but it drives me insane... it never did this before...


what to do??? has anyone else had this issue? i can't stand it. ;_;
 
At a guess, the speaker wire has become loose. Not much you can do about that.


Try plugging in headphones, see if that helps. Also turning down the volume wheel, and muting it in the software mixer, just so we can isolate something we might be able to do to "fix" it.
 
oh. i forgot to mention, it's definitely not coming from the speakers.


also, i just found out that it only makes the noise when the screen is on. when i lower the brightness all the way to off, the noise stops.


(also: it seems to change somewhat in timbre depending on the brightness. not sure what to make of that, except that it's almost definitely something to do with the screen).


(also also: turning it on from a cold boot, the noise doesn't start right away; in fact it's not until the blue pandora logo goes away that it starts. very weird)
 
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Oh, a non-sound related sound...


Well, brightness of the LCD is performed with a PWM, pulse width modulation. That is, rather than reducing the power going to the backlight, it turns it on and off really fast. It's actually more efficient to do this way in many cases.


So the brighter it is, the longer the "on" pulse, the higher the frequency (I think). You could actually be hearing the light turn on and off now. I've got a really really old florescent bulb, takes a few seconds to "warm up", but once it does you can actually hear a very low (probably 60hz) buzzing come from it. It didn't used to, this is just the nature of florescent as it wears out. I can theorize that the drop caused some damage to the backlight, just enough that you can now hear it, but not so much to actually do anything noticeable. If that's the case, the screen itself is simply broken and will need to be replaced, sorry to say. I think it's $100 or so for a new one.


Alternatively, thinking about it now, it may simply be a loose wire, and the pitch you're hearing is tiny bit of electricity arcing across to the backlight. I kind of doubt this scenario though, as if there was one loose wire, there'd surely be other signs of it, at the least the backlight flickering out completely.


I very much hope I'm wrong, but based on the description of it being linked to the backlight, it definitely sounds like damage to the said backlight and it needs to be replaced. :( Unless you've got more clues or someone else has an idea.
 
arrrgggh, that would suck. i can say that it doesn't seem to change pitch depending on brightness... it just changes in tone. i don't have it with me at this exact moment, but i think it's a somewhat sharper sound when brighter, and more muted when darker.


a loose wire would be nice i guess since it could be repaired somewhere here (by a friend though, i learned a long time ago that i should not be trusted with soldering irons), rather than mailing it back over a continent and an ocean and shelling out 100 : /
 
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