# Delay DSP crackles when when automating feedback/delay/wet
**URL:** https://qa.fmod.com/t/delay-dsp-crackles-when-when-automating-feedback-delay-wet/11076
**Category:** FMOD Studio
**Created:** [July 18, 2013, 2:15pm UTC](https://qa.fmod.com/t/delay-dsp-crackles-when-when-automating-feedback-delay-wet/11076 "2013-07-18T14:15:02Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@markmarijnissen](https://qa.fmod.com/u/markmarijnissen)
#### Post date: [July 18, 2013, 2:15pm UTC](https://qa.fmod.com/t/delay-dsp-crackles-when-when-automating-feedback-delay-wet/11076/1 "2013-07-18T14:15:02Z")
Hi,
I am sending up to 60 updates/second to FMOD to dynamically modulate Delay DSP parameters (delay, feedback, wet level). In doing so, the audio crackles.
In other instances, I am updating reverb or pitch. Here, the performance is superb and no crackling occurs.
Something tells me the crackles are to be expected when messing with the delay time (since I believe delays are implemented using circular buffers, and constantly setting and changing such buffer creates “missing” audio, which sounds as a crackle).
Could you perhaps tell me more? Is this a bug or is messing with the delay time so much an obvious “don’t do”.
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### Author:  [@geoff](https://qa.fmod.com/u/geoff)
#### Post date: [July 19, 2013, 4:16am UTC](https://qa.fmod.com/t/delay-dsp-crackles-when-when-automating-feedback-delay-wet/11076/2 "2013-07-19T04:16:59Z")
Hi,
Could you reproduce the problem in a test case, perhaps by modifying the simple\_event sample? It would help us track down the issue you describe.