# OpenSL vs AudioTrack on Android API 26+ (avoiding AAudio) **URL:** \ **Category:** FMOD Engine\ **Created:** [October 2, 2025, 7:07pm UTC](https://qa.fmod.com/t/opensl-vs-audiotrack-on-android-api-26-avoiding-aaudio/23421 "2025-10-02T19:07:14Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![sviudes](https://avatars.discourse-cdn.com/v4/letter/s/dec6dc/32.png) [@sviudes](https://qa.fmod.com/u/sviudes)\ **Post date:** [October 2, 2025, 7:07pm UTC](https://qa.fmod.com/t/opensl-vs-audiotrack-on-android-api-26-avoiding-aaudio/23421/1 "2025-10-02T19:07:14Z")
I’m using the FMOD Core API on Android. On some devices, System\_Init() takes 400 ms or more when the output is AAudio. For my case, I prefer to avoid AAudio for now. That leaves me with OpenSL or AudioTrack. I prefer OpenSL because it offers finer granularity, but I’m not sure if it is safe to use it on every device my app can run on (API 26+). Is it safe to always use OpenSL on API 26+ devices? If not, is there a way to ask FMOD which one (OpenSL vs AudioTrack) is better for the current device, like calling init with AUTODETECT but excluding AAudio? If not, what criteria should I use to decide between OpenSL and AudioTrack? Thanks! ---
**Author:** ![Connor\_FMOD](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/connor_fmod/32/3685_2.png) [@Connor\_FMOD](https://qa.fmod.com/u/Connor_FMOD)\ **Post date:** [October 6, 2025, 8:43am UTC](https://qa.fmod.com/t/opensl-vs-audiotrack-on-android-api-26-avoiding-aaudio/23421/2 "2025-10-06T08:43:51Z")
Hi, There was a known issue with slow AAudio start up times which has been solved in the most recent release: [FMOD Engine | Welcome Revision History](https://fmod.com/docs/2.03/api/welcome-revision-history.html#:~:text=Core%20API%20%2D%20Android%20%2D%20Fixed%20slow%20startup%20times%20when%20using%20AAudio.). Would it be possible to update to the latest to confirm if the issue persists? ---
**Author:** ![sviudes](https://avatars.discourse-cdn.com/v4/letter/s/dec6dc/32.png) [@sviudes](https://qa.fmod.com/u/sviudes)\ **Post date:** [October 8, 2025, 5:01pm UTC](https://qa.fmod.com/t/opensl-vs-audiotrack-on-android-api-26-avoiding-aaudio/23421/3 "2025-10-08T17:01:58Z")
> [@Connor\_FMOD](#): > > There was a known issue with slow AAudio start up times which has been solved in the most recent release: [FMOD Engine | Welcome Revision History](https://fmod.com/docs/2.03/api/welcome-revision-history.html#:~:text=Core%20API%20%2D%20Android%20%2D%20Fixed%20slow%20startup%20times%20when%20using%20AAudio.). Would it be possible to update to the latest to confirm if the issue persists? I’m currently using **FMOD Engine 2.03.09** , which according to the changelog already includes the fix for “slow startup times when using AAudio.” On a **Pixel 9A** , AAudio still takes around **350 ms** to initialize, while OpenSL only takes about **50 ms**. I understand the difference may not be huge, but AAudio doesn’t provide any clear advantage for my use case, and I need to minimize initialization time as much as possible. ---
**Author:** ![Connor\_FMOD](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/connor_fmod/32/3685_2.png) [@Connor\_FMOD](https://qa.fmod.com/u/Connor_FMOD)\ **Post date:** [October 12, 2025, 10:41pm UTC](https://qa.fmod.com/t/opensl-vs-audiotrack-on-android-api-26-avoiding-aaudio/23421/4 "2025-10-12T22:41:19Z")
Thank you for confirming. Are you able to reproduce the issue with the included android API examples in the FMOD Android Engine download: `fmodstudioapi20309android\api\core\examples\androidstudio\cmake\play_sound` How are you testing the initialization time? Any reproduction steps would be great! ---
**Author:** ![sviudes](https://avatars.discourse-cdn.com/v4/letter/s/dec6dc/32.png) [@sviudes](https://qa.fmod.com/u/sviudes)\ **Post date:** [October 13, 2025, 3:46pm UTC](https://qa.fmod.com/t/opensl-vs-audiotrack-on-android-api-26-avoiding-aaudio/23421/5 "2025-10-13T15:46:18Z")
Thank you. I reproduced it using the sample you mentioned. I added simple logging around `System::init()` and switched the output explicitly via `System::setOutput()`. Changes in `play_sound.cpp:` ```auto #include #define LOGI(...) __android_log_print(ANDROID_LOG_INFO, "FMODPlaySound",__VA_ARGS__) // in FMOD_Main(): FMOD_OUTPUTTYPE desiredOutput = FMOD_OUTPUTTYPE_OPENSL; // or FMOD_OUTPUTTYPE_AAUDIO result = system->setOutput(desiredOutput); ERRCHECK(result); LOGI("[Init] About to call system->init(32, FMOD_INIT_NORMAL, ...) with desiredOutput=%d", (int)desiredOutput); result = system->init(32, FMOD_INIT_NORMAL, extradriverdata); ERRCHECK(result); LOGI("[Init] Finished system->init()"); ``` (And linked `-llog` in `Android.mk`.) **Logs** > AAudio: **~519 ms** (961 − 442): ```auto 2025-10-13 17:19:40.442 22172-22233 FMODPlaySound org.fmod.example I [Init] About to call system->init(32, FMOD_INIT_NORMAL, ...) with desiredOutput=18 2025-10-13 17:19:40.961 22172-22233 FMODPlaySound org.fmod.example I [Init] Finished system->init() ``` > OpenSL: **~47 ms** (270 − 223): ```auto 2025-10-13 17:22:00.223 23163-23197 FMODPlaySound org.fmod.example I [Init] About to call system->init(32, FMOD_INIT_NORMAL, ...) with desiredOutput=12 2025-10-13 17:22:00.270 23163-23197 FMODPlaySound org.fmod.example I [Init] Finished system->init() ``` This matches what I see in my app: AAudio ~500 ms vs OpenSL ~50 ms on this device. For my use-case I’m optimizing cold start, and I don’t see a functional advantage from AAudio here. ---
**Author:** ![Connor\_FMOD](https://yyz2.discourse-cdn.com/flex036/user_avatar/qa.fmod.com/connor_fmod/32/3685_2.png) [@Connor\_FMOD](https://qa.fmod.com/u/Connor_FMOD)\ **Post date:** [October 21, 2025, 4:31am UTC](https://qa.fmod.com/t/opensl-vs-audiotrack-on-android-api-26-avoiding-aaudio/23421/6 "2025-10-21T04:31:27Z")
Thank you for testing that and sharing your code. I have been able to reproduce the same times. I will pass this info on to our development team. However, I will note our docs which addresses latency on Android: [FMOD Engine | Platforms Android - Audio Latency](https://fmod.com/docs/2.03/api/platforms-android.html#audio-latency). > [@sviudes](#): > > Is it safe to always use OpenSL on API 26+ devices? As OpenSl has been deprecated: [https://developer.android.com/ndk/guides/audio/opensl](https://developer.android.com/ndk/guides/audio/opensl), I cannot say that it will be safe on all devices. You could attempt to initialize the FMOD system with OpenSL and on failure resort to AAudio? > [@sviudes](#): > > If not, is there a way to ask FMOD which one (OpenSL vs AudioTrack) is better for the current device, like calling init with AUTODETECT but excluding AAudio? Unfortunately, you cannot filter outputs when using `AUTODETECT`, I could suggest this to our development team to look into however. I will link to a post where some options for dealing with latency were discussed: [High latency with AAudio - #2 by jeff\_fmod](https://qa.fmod.com/t/high-latency-with-aaudio/19196/2). ---
**Author:** ![sviudes](https://avatars.discourse-cdn.com/v4/letter/s/dec6dc/32.png) [@sviudes](https://qa.fmod.com/u/sviudes)\ **Post date:** [October 22, 2025, 5:01pm UTC](https://qa.fmod.com/t/opensl-vs-audiotrack-on-android-api-26-avoiding-aaudio/23421/7 "2025-10-22T17:01:54Z")
Thanks for the detailed reply, and for the link about latency. Just to clarify, my concern here isn’t about **latency during playback** , but rather the **initialization time** of the FMOD system. For now, I’ll continue using **OpenSL** , with a **fallback to AUTODETECT** if either `setOutput()` or `init()` return an error. That seems like the safest balance for the moment. It would be great if future versions could either **match the initialization speed** between AAudio and OpenSL, or provide a way to **automatically skip AAudio** during output selection. Thanks again for your help and for forwarding the info to the dev team.