# FMOD\_STUDIO\_INIT\_SYNCHRONOUS\_UPDATE and FMOD\_INIT\_MIX\_FROM\_UPDATE **URL:** \ **Category:** FMOD Engine\ **Tags:** ios\ **Created:** [July 30, 2026, 7:47am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437 "2026-07-30T07:47:31Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![marko.ravnjak](https://avatars.discourse-cdn.com/v4/letter/m/c67d28/32.png) [@marko.ravnjak](https://qa.fmod.com/u/marko.ravnjak)\ **Post date:** [July 30, 2026, 7:47am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/1 "2026-07-30T07:47:31Z")
FMOD 2.03.14 with custom engine integration I’ve setup fmod integration, got everything to build. Audio works on windows, mac os, android but not ios. On ios i get no errors, everything inits ok. Initially I added the FMOD\_STUDIO\_INIT\_SYNCHRONOUS\_UPDATE flag because i was experiencing some slow loading of large number of banks (~100), I guess due to the internal thread ticking. After I set the flag, bank loading was “instant”. After that point, we started testing on devices and figured out that ios is not working. Create/play event “works”, status is playing, but time position stays on 0 all the time. I pooled internal DSP clock and that one also stays at 0 all the time. After some testing I added FMOD\_INIT\_MIX\_FROM\_UPDATE and this made things “go”. Did I miss anything, is this intentional? ---
**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:** [August 6, 2026, 5:37am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/2 "2026-08-06T05:37:17Z")
Sorry for the delayed response! It’s not intentional that synchronous update requires `FMOD_INIT_MIX_FROM_UPDATE`, so it’s likely that something is blocking the mixer in general, or processing for the events in question. Can I get you to use [`Debug_Initialize`](https://www.fmod.com/docs/2.03/api/core-api-common.html#debug_initialize) to set your debug flags to `FMOD_DEBUG_LEVEL_LOG`, and provide me with a log from when the issue is occurring? Also, I’d recommend using [`Studio::Bank::getLoadingState`](https://www.fmod.com/docs/2.03/api/studio-api-bank.html#studio_bank_getloadingstate) to ensure that your banks are being loaded as expected, since changing to synchronous update shouldn’t immediately resolve bank loading issues. ---
**Author:** ![marko.ravnjak](https://avatars.discourse-cdn.com/v4/letter/m/c67d28/32.png) [@marko.ravnjak](https://qa.fmod.com/u/marko.ravnjak)\ **Post date:** [August 11, 2026, 10:30am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/3 "2026-08-11T10:30:24Z")
Hi, I’ve uploaded app-log-ios-26.txt audio works on on older devices/OS (16,17) while later (18,26) don’t produce any audible output. I see some: Insufficient buffer size detected logs ---
**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:** [August 14, 2026, 4:16am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/4 "2026-08-14T04:16:53Z")
Thanks for the log! Historically, the “insufficient buffer size” warning on iOS generally indicates that the buffer size expected by iOS is larger than what FMOD is producing, which the log appears to indicate. This had commonly occurred when suspending the application due to iOS hardware swapping from the smaller the FMOD application is using to a larger buffer, and failing to swap back when resuming. I suspect `FMOD_STUDIO_INIT_SYNCHRONOUS_UPDATE` may be causing the same problem when you’re not using `FMOD_INIT_MIX_FROM_UPDATE`. I’d recommend increasing FMOD’s DSP Buffer Size (which has usually been from 512 → 1024) and seeing whether it resolves the issue. ---
**Author:** ![marko.ravnjak](https://avatars.discourse-cdn.com/v4/letter/m/c67d28/32.png) [@marko.ravnjak](https://qa.fmod.com/u/marko.ravnjak)\ **Post date:** [August 20, 2026, 7:45am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/5 "2026-08-20T07:45:43Z")
I’ll try larger buffer today; Just to clear up, I removed both FMOD\_STUDIO\_INIT\_SYNCHRONOUS\_UPDATE`and `FMOD\_INIT\_MIX\_FROM\_UPDATE. You recommend using 1024x4? Or should 1024x2 be enough? ---
**Author:** ![marko.ravnjak](https://avatars.discourse-cdn.com/v4/letter/m/c67d28/32.png) [@marko.ravnjak](https://qa.fmod.com/u/marko.ravnjak)\ **Post date:** [August 20, 2026, 8:12am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/6 "2026-08-20T08:12:56Z")
Does idle pool “handle” also streaming sounds? ---
**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:** [August 21, 2026, 5:10am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/7 "2026-08-21T05:10:40Z")
> [@marko.ravnjak](#): > > You recommend using 1024x4? Or should 1024x2 be enough? I’d recommend using `1024x4`. > [@marko.ravnjak](#): > > Does idle pool “handle” also streaming sounds? No, only samples. If increasing the buffer size works, if you haven’t already you may also wish to try modifying any code you have that interacts with AVAudioSession to explicitly call setPreferredIOBufferDuration and setPreferredSampleRate on initialization, which should help in most cases where iOS doesn’t give you back the buffer size you require. Example code for this can be found in the suspend/resume example that ships with the FMOD Engine iOS examples. ---
**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:** [September 1, 2026, 5:57am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/8 "2026-09-01T05:57:13Z")
Just following up on this - were you able to resolve the problem by increasing the buffer size? Have you run into any other issues? If so, please feel free to let me know. ---
**Author:** ![marko.ravnjak](https://avatars.discourse-cdn.com/v4/letter/m/c67d28/32.png) [@marko.ravnjak](https://qa.fmod.com/u/marko.ravnjak)\ **Post date:** [September 1, 2026, 7:35am UTC](https://qa.fmod.com/t/fmod-studio-init-synchronous-update-and-fmod-init-mix-from-update/24437/9 "2026-09-01T07:35:17Z")
hei, yes. buffer increase solved the issue.