Video playback strange Noise (hissing) issue

I've noticed this as well. I'm not sure what is going on, but there seems to be quite a few problems with the new release of the iPhone 4.

I noticed this just today myself. I made a video on my iphone 4, and on playback there is a whirring/hissing/vintage "reel" sound. I posted to YouTube directly from the phone, and the noise is present there as well--I have not yet downloaded it directly to my MacBook to see if it "disappears".

Update: downloaded it to my iPhoto, plays with the same background noise. I'm not sure I would call it a hissing, though. It really is best described as that "projector" type of sound you hear when seeing a movie on an old projector...

I have this strong hiss as well. It is also on the voice memos. When I copy to the computer, it is diminished considerably.

I wonder if we have a bad batch or not enough people have tested theirs yet?

I am getting this noise on mine too ( would definitely say it's a hiss) haven't tried transferring to my pc yet to see if its still there.

There's an even quicker way to test it. Put earphones on and listen to the playback (of video or voice memo). I don't have the hiss then, so it's a speaker issue. I looked to see if there were any settings that I could change to change the speaker but didn't see any.

I'm having the same issue and all of a sudden notice that the microphone is muted when trying to use speakerphone. Makes no difference when you mute and unmute via the touchpad, the mike goes dead when using speakerphone. I'm thinking these two problems may be related. Anybody else notice this?

The hardware is not faulty. It's the way the iPhone 4 was designed.

I'm an iPhone developer and through some casual testing I've concluded that the iPhone 4 is doing some kind of DSP processing on all audio output that goes through the speaker, boosting perceived volume through EQ as well as added reverb in certain situations. This is why a lot of non-musical audio sounds hissy, boxy, echoey. If in your software you reduced the software volume playback setting to about 0.35 (default is 0.5), the problem goes away dramatically. If you plug in headphones the problem goes away right away.

The speakers are unfortunately of lower quality than the 3GS. Through the DSP processing, some situations the audio will sound "better", "clearer" but it definitely lacks the authentic presence than the 3GS had.

I transferred 3 videos to my windows pc and the background noise is still there so its not a speaker issue on mine.

I just tried using the mic built into the headset and the problem was not there. Retried with mic built into the phone and the problem is back. The mic built into the phone works fine when making a normal phone call unless I activate speakerphone. Phone mic does not operate with speakerphone. It has nothing to do with proximity sensitivity since it's away from my face and I can watch the mute indicator show off and on with no difference at either setting. So, the mic does work for normal call. Not a hardware problem. I have an audio spectrum program loaded and the mic seems to work for that too. Hopefully the first update will fix this

Thank you, eeeechuta, that's helpful. So from what I can tell from your message, it would be possible for Apple to do a software fix on this? Any thoughts on why they didn't in the first place?

I'm sure Apple could do something in software to alleviate the hissing.

In my application for example, I can make the iPhone4 and the 3GS sound more similar if I reduce the playback volume by 30% in software for the iPhone 4 speaker only. At this point both phones have approximately the same volume when the hardware volume is at maximum. But mysteriously the echoing and hissing also go down dramatically too on the iPhone 4.

Apple may consider this new sound a "feature" and not a problem, because this method does seem to make smaller sounds more audible from other audio sources like games and music. Also this problem only affects playback of audio sources that originally contain noise, like video capturing and the voice memo application. In other words, the new way has good and bad points, but in my person opinion I like the 3GS sound slightly better.

Hi Johannes,

I am experiencing exactly the same problem you are describing. Haven't seen your post before so I created a new subject:

http://discussions.apple.com/thread.jspa?threadID=2500205&tstart=0

I really hope this can be fixed by software and that this is not hardware related.

Best Regards
Michael