I'm currently working on a small project where I'm loading 16bit wave files with a sample rate of 44100Hz. In normal playback the audio seems fine but as soon as I start to play with things like amplitude size to change the volume it starts giving a little bit of static noise.
What I'm doing is getting a sample from the buffer in the case of this 16bit type a short, converting this to a float in the range of -1 to 1 to start doing mixing and other effects. In this I also change the volume, when I just multiply it by 1 giving the same output its fine but as soon as I start to change the volume I hear the static noise. It happens when going over 1.0 as well as going below 1.0. And it gets worse the bigger or smaller the scale.
Anyone an idea how to reduce or remove the noise ?
I found the flaw, I was abstracting different bit data types by going to their data using char*, I did not cast the usage of it to the correct datatype pointer. This means bytes were cut off when giving it data. This created the noise and volume changing bugs amongst others.
A flaw of my implementation and me not thinking about this when working with the audio data. A tip for anyone doing the same kind of thing, keep a good eye when modifying data, check which type your data is when using abstractions.
Many thanks to the guys trying to help me, the links were really interesting and it did learn me more things about audio programming.