MBP SR Headphone jack hiss

Hey guys, I recently bought a MBP and was wondering why the sound quality was so bad when plug my headphones into it. Well right now im studying at hte school library, and trying to listen to a little ambient/classical music, and i noticed that there is a weird hissing noise in the background even when the computer is not outputting any sound. Also, if you listen closely everytime you change the volume, it starts to make some beeping noises. and every other volume bar, it makes the same kind of hissing/beeping. This is getting really annoying since I'm a LITTLE bit of an audiophile. I just want some clean ambiance. Some peoplesay is because the magsafe magnet is so close to the headphone jack that its causing this constant hissing, but if it thats the case, its undoubtedly unfixable. So poor design apple?! I just want this resolved, I didnt have this problem with the Macbook at all. I also have a usb soundcard, but I'd rather use the stock headphone jack since its suppose to be better anyway, but not if the signal keeps getting interrupted by the danged magnet! Anyway, if anyone has any suggestions it would be most appreicated.

 

Have you run Software Update - the last one I did included an audio patch, but I don't know if it solves this problem.

 

yea i ran the software update, my MBP is completely updated. Also the hissing is present in windows too, if you listen to it while its booting, when the audio driver is loaded or turned on the hissing starts. Its not as prominent as it is in windows for some reason though. Much more noticable in osx

 

does using the USB sound card eliminate these noises?

 

I got a similar problem. Sound quality and microphone (on the head set not build in) is not so great. Under bootcamp in Windows XP it is much much better then in OSX so it cant be a hardware problem.

 

apparently the hissing sound has to do with the logic board. A lot of them have been affected by this.

 

Any way to fix it? I plan on using my MBP as portable mp3 player when I am studying...a hissing sound would be terrible. Does the hissing sound occur WHILE listening to music?

 

I haven't tried to use my USB sound just yet. But this only really happends with low powered headphones (ear buds) at low volumes, and it can over power the music if the music is playing really low (like when i play music for ambience when I study). If your playing music and normal listening volumes for recreation, you shouldn't notice this problem.

 

Do you hear the hiss with higher quality headphones?

I've seen similar issues discussed with some PC laptops as well (I think there was a discussion of a hiss with the headphone jacks on Inspiron 1520's), and I think some people also mentioned that they didn't have the issue with higher quality headphones.

 

Not sure if the quality of the headphones is really the issue more like the amount of Ohms it takes to power the headphone. I hear the hiss at lower volumes on my in-ear headphones (can be considered high quality) but not on my over the ear headphones (Sennheiser HD 595's). But it takes almost twice as much to power the bigger ones so this hissing is not as prominent.

 

sorry but it seems like it is a hardware problem with no easy fix,

from http://www.macintouch.com/reviews/mbp15led/:

 

don't have mbp, yet, so can't comment on that specific hardware, but i can provide some more general info.

in the realm of professional audio, it is considered imperative to get your analogue to digital and digital to analogue (AD and DA respectively) outside the computer (a breakout box) in order to obtain the cleanest signal possible. this is because analogue signals are susceptible to electromagnetic interference (EMI). prime sources of EMI include voltage transformers, inductors, and in laptops LCD power inverters.

basically, putting a DA converter within a laptop chassis next to these kind of components is inevitably going to result in some level of background noise. how much varies with the quality of components and more importantly, proximity to EMI sources. this is a factor that affects ALL laptops to varying degrees.

as noted previously, the sennheiser headphones have a considerably higher impedance than earbuds, and so the low power EMI has a tougher time getting the speakers to move.

bottom line, this is not just a special apple problem, or something unique to the new mbp's (although it's intensity may have increased with the new design - i can't say personally). if it's enough to bother you, the only way you will ever get rid of it properly is by putting your converters in a shielded box on their own, away from EMI sources.

 

I did a little testing with my new MBP 2.2....

Using my Creative EP-630, the hiss was very noticeable when there were no sounds. Playing an mp3 at normal volumes masks the sound but at a softer level the hiss is somewhat noticeable.

Using my Sennheiser PC 150s, the hiss disappeared completely whether there was sound or no sound.

Now I'm no audio expert so I'm kinda taking a stab and guessing the input impedance is the important spec because it was the only one measured in ohms (ohms being mentioned in this thread as the difference between hearing hiss or not). The Creative EPs have 16 ohm input impedance whereas the PC 150s have 32 ohm.

Using this logic, shouldn't something like a Etymotic Er6 be fine considering it has a 48 ohm impedance? Anyone got some er6is and a mbp?

 

On mine, there's a hissing sound even if I have headphones that go over my ears. Is that unusual?

 

Naw, I can sometimes hear them on my bigger headphones too.

 

I really only notice it when I don't have music playing.

 

I used my Koss KSC-75 which have an impedance of 60 ohms and they also had minimal hiss. The sound is going to be there but it's going to be very audible to very very faint depending on what type of headphone you use.

KSC's are really cheap ($15) and it's regarded as a rite of passage for audiophiles. They sound pretty decent to me but I'm no audiophile. Can't go wrong for 15 dollars.

 

I hate to say it, but I chose Bose products for my computer work (yes I know their audio woes) because they perfectly filter both MBP and SigmaTel noise issues. Unfortunately, they accent the terrrrrible audio quality of the nano.

 

Sorry to revive this relatively dead thread, but I figure its better than starting a new one of the same topic.

I just got a 15" 2.4 MBP and I'm having the same hiss issue. It makes my Super.Fi 5 Pros near unusable without an attenuator.

My main question is what headphones have you guys hound work well with the MBP? I'm looking for something sealed, very comfortable, and also portable. A right angle plug would be preferred as well.

 

I have no experience with Apple Customer Service before. Just wanna clarify. So I have this hissing problem, will Apple replace my unit?

 

No, they all have the same problem.

 

I think, as stated before, this is a general problem with laptops. I have the same issue sometimes with my M90. I would assume that the problem has gotten worse on the Macintels because they use the Intel HDA (Sigmatel) onboard sound processor, which isn't of the greatest quality. It's pretty much standard on all Intel-based laptops these days.

 

Good point, making me wonder why nobody uses a shielded daughterboard for sound.

Have things been better in the past on previous MBP, and the Powerbook before that? Sound accuracy aside, strictly with hissing and tones, is the SR MBP better, worse, or about the same?

I miss PCMCIA

 

I got the impression that it was worse than the powerbooks. From what I hear the powerbooks also had a more powerful output.


Anyway, I ended up getting some Sennheiser HD280 Pros. They work well, but I wish they had a right angle plug.

 

ya im having this problem too only its in my car. I use a Kensington 150w inverter to charge my mbp and was hoping to be able to use my car's stereo aux port. I've used headphones before and didnt hear anything but for some reason my car stereo was outputting this incredibly loud and annoying hiss. When i removed the magsafe the noise went away. This really stinks as I wanted to listen to music or play a game while waiting in my car. Guess i have to settle with the built in speakers or not charge while outputting sound.

Edit: Been searching for a fix. Someone posted this in the apple support discussions. I'll give it a shot and order one. Apparently works with a cheap one from radio shack too.
"The Fix
The fix is actually surprisingly easy: all you need to do is increase the impedance of your headphones! To do this, you'll need to either buy or make an adapter. I chose to buy one, the Shure Level Attenuator Volume Control EA650. Cheapest I could find it was from some guy on eBay. Shure makes good quality products, and at $14 shipped it's not that expensive. It connects between your computer and your headphones, and only a quarter turn on the volume knob eliminated the hiss and static for me."

 

The Powerbooks and the CoreDuo and Core2Duo Models did not have this issue, I had both of them. The final stage in the amplifier of the SR MBP simply has a higher gain thus more noise. The pieps and beeps whenever you stop playing a song (i.e. in iTunes) come from something else but are natural to the machines design.
Listen to it:
http://www-users.rwth-aachen.de/megajoule/temp/rauschenundpiepen.mov

With low impedance head-phones you will have to use an attenuator to have a noise free Audio-Experience. My Etymotics ER4P produces an insane level of noise so I built myself an attenuator like this:


i.e.
R1 = 3,3Ω
R2 = 27Ω

With the Sennheiser HD600 I got I can barely make anything out. They have 300Ω though, compared to the 27Ω of my Etymotics.


I'm really pissed that Apple went this way, earlier MBP and Powerbooks were far better... whoever wants to drive anything big should use an external Amp. (say hello to Mr. Jobs who has bad hearing!!!) The speakers in the SR MBP are worse too, less mid and a lot less high freq. response! More bass though.... Liked the ones of my earlier MBP far better.
I'm fairly sure this issue can never be solved with a firmware Upgrade....

 

hmm noob when it comes to stuff like this. There a guide on making your own attenuator that you would recommend?