The following is a letter I wrote to Apple Accessibility regarding some interesting behavior that I kept track of since not long after I received my shiny, new iPhone 3GS last June. While the letter certainly ventures into geekdom and may even border on obsession, I thought I’d share it nonetheless and see if others may have observed the same … or not. Note that the issues discussed don’t necessarily have anything to do with accessibility, but since I am a VoiceOver user and that the behavior differs when VoiceOver is used versus when it is not, the Accessibility Team is what first came to mind. I imagine, if necessary, it was forwarded appropriately. Here’s the letter:
… I want to explain something to you that may be a little challenging to put into words, so please bear with me. Through a bit of testing, I have determined that, when the iPhone is being used with VoiceOver off, the audio system behaves differently than when it is used with VoiceOver running. One of the big clues which prompted me to experiment and thus has aided me in the process is the slight hiss that is audible through the iPhone’s small speaker on the bottom left edge of the iPhone. When VoiceOver is off, the phone will produce various sounds, as normal, when locking, unlocking, checking mail, receiving alerts, ETC. About 5 seconds after each sound, the softly audible hiss that I correlate with the audio amplification turns itself off. If another sound is made, it switches back on, makes the sound, and if no other sounds occur, the 5 seconds is reached and off it goes again. This seems logical and I imagine it saves battery as, if it were to stay on, it would continuously require more power.
With VoiceOver running, however, this behavior is different. In one respect, it seems understandable that behavior would change since VoiceOver would be doing a lot of speaking. It wouldn’t make sense for 5-seconds of inactivity to switch amplification off only to have the system be engaged a second or two later to speak more information. However, I have noticed that the system works unpredictably when VoiceOver is on in terms of turning the hiss sound off after inactivity. Sometimes, it will take about 10 seconds of inactivity before I hear the speaker hiss stop. This seems to happen most often when the battery level is high (anywhere from 100-85 %). Otherwise, the hiss never stops. It will remain even when the iPhone hasn’t produced any sound whatsoever for hours on end. Putting the phone to sleep makes a difference, also. In most cases, the hiss would have more of a chance of stopping when the phone was put to sleep. This is highly unpredictable, as I mentioned. Sometimes, I’ll pick up the phone after several hours and the audio hiss is not there.
Perhaps you already have awareness of this strange phenomenon because I have noticed different behavior in the 3.1.3 firmware update. It seems a lot better now, but still a little unpredictable. The hiss sometimes seems to last, but not for too long before it switches off.
Another thing that I’d like to address is that the audio volume for alerts is lower when VoiceOver is on versus when VoiceOver is off. It would be great if the system alert sounds would retain the system volume setting regardless of whether or not VoiceOver is running. …
That’s the gist of the letter aside from thanking them for the awesome job they’ve been doing. Since then, I’ve concluded that there isn’t much change in the newest iPhone OS release after all.
I feel that all of this, as quirky as it sounds, is a legitimate factor in the battery’s rapid power drain. I haven’t yet heard back from Apple regarding this, but perhaps it is being addressed along with the multitude of other fixes and features that will be incorporated into the next release. Now that we have a slight idea of what is coming, I await with eager anticipation for the release of iPhone OS 4. 😉
