# Recommended method for rendering FMOD Studio event waveforms

**URL:** <https://qa.fmod.com/t/recommended-method-for-rendering-fmod-studio-event-waveforms/24328>\
**Category:** FMOD Engine\
**Tags:** cpp, godot, core-api\
**Created:** [June 10, 2026, 8:34pm UTC](https://qa.fmod.com/t/recommended-method-for-rendering-fmod-studio-event-waveforms/24328 "2026-06-10T20:34:18Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![d3vi1i5hv0id](https://avatars.discourse-cdn.com/v4/letter/d/e9c0ed/32.png) [@d3vi1i5hv0id](https://qa.fmod.com/u/d3vi1i5hv0id)\
**Post date:** [June 10, 2026, 8:34pm UTC](https://qa.fmod.com/t/recommended-method-for-rendering-fmod-studio-event-waveforms/24328/1 "2026-06-10T20:34:19Z")

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Hello,  
I’m currently working on the Godot 4.5 source code, making a custom FMOD engine module. The rest of the integration is unimportant in its implementation, but I am currently dealing with rendering a waveform of Studio 2.03.13’s output of the provided event.

I’m using `FMOD_OUTPUTTYPE_NOSOUND_NRT` for the output type and initializing with the studio flags `FMOD_STUDIO_INIT_SYNCHRONOUS_UPDATE` and the core flags `FMOD_INIT_STREAM_FROM_UPDATE | FMOD_INIT_MIX_FROM_UPDATE`.

For the rendering itself, I’m setting up a capture DSP (attached to the master channel group) with a read that only appends the inbuffer across all channels to an external array and copies them to the outbuffer afterwards (for which I can share any specific code as needed).

The issue I’m having with this process is that it’s producing inconsistent and unclean results. Rendering of the waveform in-game is broken into chunks of the song, and these often have leading silence (which I trim at render-time to preserve the requested duration of render) and, more importantly, incorrect data or even no data at all for no apparent reason.

For capturing an event’s final output at a position for a duration, is there a recommended method that I should consider? If not, are there any issues with things I could be missing, like initialization flags or other setup? Again, I can share any code as needed, but the module code is uploaded to my profile for viewing.

Thank you.

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<div class="post-metadata">

**Author:** ![Leah\_FMOD](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/leah_fmod/32/3685_2.png) [@Leah\_FMOD](https://qa.fmod.com/u/Leah_FMOD)\
**Post date:** [June 15, 2026, 6:57am UTC](https://qa.fmod.com/t/recommended-method-for-rendering-fmod-studio-event-waveforms/24328/2 "2026-06-15T06:57:04Z")

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Thanks for uploading your module code. At a glance, your capture DSP and read callback seem fine. Our general recommendation for capturing audio from a specific channel is to use a capture DSP in the way you have. The alternative is to use FMOD\_OUTPUTTYPE\_WAVWRITER or the NRT version to capture the whole mix, which may be an alternative for you if you’re only playing back a single event at the time. It’d difficult to diagnose exactly what the issue is without more info, so I have a few questions:

- Does using Studio default mixing init flags (i.e. asynchronous update and mixing) or a real-time output type make any difference?
- Are you able to reproduce the issue with the WAVWRITER or WAVWRITER\_NRT outputs?
- Can I get you to you set FMOD’s logging level to “LEVEL\_LOG” with [Debug\_Initialize](https://www.fmod.com/docs/2.03/api/core-api-common.html#debug_initialize), and upload a log where the issue occurs?
- If possible, can I get you to upload the recorded audio file of the issue from the capture DSP, and the “correct” audio from an external program like OBS, so that I can compare the two?