<DUO 13> The electronic noise from the adapter and laptop

I bought a DUO 13(i7 4650u model) from Sony online store and have been noticing this annoying electronic noise coming
from the bottom of laptop and the adapter(when plug the adapter).When using battery is very quiet.
It sounds like 'j e j e j e', When running a large program is more obvious.this is I recorded noise file( https://copy.com/Uyi6LqkmWPlM).
It's not very loud but most of the time I use it during the night so when the environment is very quite it gets really really annoying.
So I changed a new Duo 13 from sony online store, But I also found that noise exist.
I have been to the retail store tried other DUO13s(i5 model), found that do not have this noise.
Do not know if you have not encountered this noise?

 

So you had your Duo 13 replaced and the noise is still there? Going to the retail Sony Stores, you cannot hear the noise? Have you tried your Duo at another location? I'm thinking it could be some kind of interference.

 

yes. the replaced duo13 still have the noise. retail store do not have i7 model duo 13, i tried i5 model and is very quiet.I tried my Duo 13 in many place(include retail store), the noise is still here. I wonder is it a particular batch problem?

 

Hi,

I've bought the core i7 4500u.

I can confirm the noise and in standby a "knock knock knock"-Sound.
For about 2 weeks I let repair the duo13 at a sony-rapair-center.
They changed the motherbaord. - The noise is still there.

 

Haven't been on these forums for ages. But thought I'd pitch in nonetheless after some lurking.

To start. The 'je-je-je' sounds. High pitched, electrical sounds right? I can relate to this in regards to the AC adapter.
This comes down to how 'noisy' your AC point is. Case-in-point, if I use my VGN-Z and its AC adapter at university I'll hear electrical 'fizzing' sounds coming from the adapter.

The reason?
Noise. More specifically, in a university environment, where there are MANY AC points dotted closely together (and most being used by other students for their own laptops, cellphone charging, what-have-you).

This is normal?
Yes. Not much you can do about it. But AC-DC adapters are designed to reduce noise coming from the source (the AC in this case). When it does encounter more noise than usual, it will make the sounds. The capacitors in the brick, responsible for filtering out the noise, will also run a little hotter than usual. Some would argue that the lifetime of the adapter may be affected, but I'd personally say it'll be negligible at best.

I have experienced the issue of a 'fizzing' AC adapter. At university at least. I bring and use my machine at home and the adapter is dead silent.

As for why you hear this from your laptop as well.... Not sure to be honest.
I would like to think that Sony did a good job designing their filter circuitry properly inside their newer generation laptops, but if they didn't (which I doubt)...

Possible suggestion:
Not sure about Windows 8 as I've never used it before. But have you tried going into your power settings and setting your MAX and MIN settings under PROCESSOR POWER MANAGEMENT? For example, setting both to 100%? Maybe the sounds on the laptop are due to the CPU clock constantly changing speeds (which it can depending on what the setting there is, and what you're doing in Windows).

Yeah... Hope that helps somewhat.

 

Since I've installed Win 8.1, the noise is going away! YEAH!

 

Thought someone mentioned that it was the RAID driver.

 

I'just updated the bios and then to win 8.1
I did not extra install the raid-driver.