Harsh noise on plugin start

Audio Plugins
1

My audio plugin emits an harsh high frequency noise when it starts once every 6/7 times. It is a simple wavetable synthesiser with an exponential decay envelope. The wavetable is generated by reading a .wav file, and there should be no dangling pointers as I am using only unique_pointers.
My wavetable class is modelled on the juce tutorial and the envelope is modelled on the Audio Programming Book examples
Apart from that noise on start-up the plugin works smoothly.
I know it is like searching a needle into a haystack but which other things should I keep in mind while searching for my bug?
In the plugin editor I have many images that I get as ImageCache from binary data. Could that be the problem?
P.s. I am not making the #1 beginner mistake

Thanks for any tip.

2

You can opt to return a GenericAudioProcessorEditor to remove your editor from the equation and quickly rule that out.

3

my initial guess would be that you resized some buffer (probably in prepareToPlay or so), but didn’t give it a default value of 0. if you use std::vector as audio buffer, always use the 2nd optional arg of resize to make sure that it’s not garbage values, but 0.

buffer.resize(blockSize, 0.f);

when resizing juce::AudioBuffer there’s also an option to clear it on setSize

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4

it was a good idea to try it, but noise is till there ;(

5

Sometimes it’s caused by uninitialized variables.

6

it was indeed a resized buffer and clearing the extra space with setSize solved the problem. thank you very much.

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