How to program a real-time accurate audio sequencer on the iphone?

I want to program a simple audio sequencer on the iphone but I can't get accurate timing. The last days I tried all possible audio techniques on the iphone, starting from AudioServicesPlaySystemSound and AVAudioPlayer and OpenAL to AudioQueues.

Real-time Pitch Shifting on the iPhone

I have a children's iPhone application that I am writing and I need to be able to shift the pitch of a sound sample using Core Audio. Does anyone have any example code I could look at where this is done. There are many music and game apps in the app store that do this so I know I am not the first one. However, I cannot find any examples of it being done.

Android - play sound on button click - Null pointer exception

I am trying to play a sound file on the click of a button. The sound is just 1 sec long. It plays well the first few times I click the button, but after a while it gives a NullPointerException. Here's the code:

Audio Framework: stream, strategies, devices

I am trying to get a better understanding of android audio framework (froyo onwards in particular).

How do record audio from a bluetooth headset on the iPad/iPhone?

I can hear audio from bluetooth headsets on my iPad/iPhone, but I can't record audio in Applications from the headset. Even the sample "SpeakHere" application doesn't record audio from the headset.

How can I play sound in Java?

I want to be able to play sound files in my program. Where should I look?

Android : testing a service

we are actually developping an audio service (in the android sense of the term) and we have quite of lot of tests to cover many aspects of our APIs. But we are actually wondering for good things to do to test a service efficiently.

Is it possible to convert audio file with some music notes?

I have a music file with a particular tone(music.mp4). I want to convert existing sound file (speech.mp4) into the tone which is specified in music.mp4. Its like converting a speech into some particular tone. I do not want to play both files simultaneously. I want to convert source file with help of some music file. So, output file will be converted file.

force smartphone use headset from browser?

Is there a way to force visitors in my website, that use smartphones, to heare music only through headsets? That is, force the mobile browser not play sound with the speakers?