setPreferredMixerAttributes on USB DAC can cause whole system to hang on MTK device with MTK Hi-Fi

Android version(s): Android 14 (not QPR) stock ROM
Android device(s): Any MTK device with MTK Hi-Fi enabled (I used Unihertz Jelly Max)
Oboe version: Any (reproduces on 1.9.2)
App name used for testing: OboeTester with patch on top of e3bde1b6bcf7ebba0f5461e12de87c4f12a79679

```java
diff --git a/apps/OboeTester/app/src/main/java/com/mobileer/oboetester/TestAudioActivity.java b/apps/OboeTester/app/src/main/java/com/mobileer/oboetester/TestAudioActivity.java
index f286ffbb..ff62151e 100644
--- a/apps/OboeTester/app/src/main/java/com/mobileer/oboetester/TestAudioActivity.java
+++ b/apps/OboeTester/app/src/main/java/com/mobileer/oboetester/TestAudioActivity.java
@@ -27,6 +27,7 @@ import android.content.pm.ServiceInfo;
import android.media.AudioAttributes;
import android.media.AudioDeviceInfo;
import android.media.AudioManager;
+import android.media.AudioMixerAttributes;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
@@ -46,6 +47,8 @@ import androidx.appcompat.app.AppCompatActivity;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
import java.util.Locale;

/**
@@ -631,6 +634,39 @@ abstract class TestAudioActivity extends AppCompatActivity {
public void openAudio() throws IOException {
closeAudio();

+ if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.UPSIDE_DOWN_CAKE) {
+ AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
+ List info = Arrays.asList(audioManager.getDevices(AudioManager.GET_DEVICES_OUTPUTS));
+ for (AudioDeviceInfo device : info) {
+ List attr = audioManager.getSupportedMixerAttributes(device);
+ if (attr.isEmpty()) continue;
+ attr.sort((a, b) -> {
+ if (a.getMixerBehavior() != b.getMixerBehavior()) {
+ return a.getMixerBehavior() == AudioMixerAttributes.MIXER_BEHAVIOR_BIT_PERFECT ? 1 : -1;
+ }
+ if (a.getFormat().getSampleRate() != b.getFormat().getSampleRate()) {
+ return a.getFormat().getSampleRate() > b.getFormat().getSampleRate() ? 1 : -1;
+ }
+ if (a.getFormat().getChannelCount() != b.getFormat().getChannelCount()) {
+ return a.getFormat().getChannelCount() > b.getFormat().getChannelCount() ? 1 : -1;
+ }
+ if (a.getFormat().getEncoding() != b.getFormat().getEncoding()) { // :)
+ return a.getFormat().getEncoding() > b.getFormat().getEncoding() ? 1 : -1;
+ }
+ return 0;
+ });
+ audioManager.setPreferredMixerAttributes(new AudioAttributes.Builder()
+ .setUsage(AudioAttributes.USAGE_MEDIA)
+ .setContentType(AudioAttributes.CONTENT_TYPE_MUSIC)
+ .build(), device, attr.get(0));
+ }
+ try {
+ Thread.sleep(500);
+ } catch (InterruptedException e) {
+ throw new RuntimeException(e);
+ }
+ }
+
updateNativeAudioParameters();

if (!isTestConfiguredUsingBundle()) {
@@ -811,6 +847,19 @@ abstract class TestAudioActivity extends AppCompatActivity {
updateEnabledWidgets();
onStopAllContexts();
}
+
+ if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.UPSIDE_DOWN_CAKE) {
+ AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
+ List info = Arrays.asList(audioManager.getDevices(AudioManager.GET_DEVICES_OUTPUTS));
+ for (AudioDeviceInfo device : info) {
+ List attr = audioManager.getSupportedMixerAttributes(device);
+ if (attr.isEmpty()) continue;
+ audioManager.clearPreferredMixerAttributes(new AudioAttributes.Builder()
+ .setUsage(AudioAttributes.USAGE_MEDIA)
+ .setContentType(AudioAttributes.CONTENT_TYPE_MUSIC)
+ .build(), device);
+ }
+ }
}

public void runTest() {
```

**Short description**
When stress testing open/close with preferred mixer attributes, device will progressively become more and more unresponsive until eventually hanging for minutes in buggy state (live wallpaper became black, can't open settings app - hanging forever, etc) before recovering. Presumably root cause is audioserver 100% CPU:


Please see attached video for how to reproduce

removed

To reproduce: repeatedly, open&start&close an OpenSL ES stream with 88200 sample rate and None performance mode. System will become unresponsive quickly, causing Settings app, live wallpaper and OboeTester to ANR.

Bug report ZIP
removed

**Steps to reproduce**
Please see the attached video, it was recorded on freshly factory reset test device, no device settings modified.

**Expected behavior**
No ANR, wallpaper not turning black, settings app keeps working, audioserver not 100% cpu, etc

**Actual behavior**
see above :)

**Device**
ro.product.brand = Unihertz
ro.product.manufacturer = Unihertz
ro.product.model = Jelly Max
ro.product.device = Jelly_Max
ro.product.cpu.abi = arm64-v8a
ro.build.description = sys_mssi_64_64only_ww_armv82_g78v78c2k_dfl_eea-user 14 UP1A.231005.007 V01.00.00 release-keys
ro.hardware = mt6878
ro.hardware.chipname =
ro.arch =
| grep aaudio = [aaudio.mmap_exclusive_policy]: [2]
[aaudio.mmap_policy]: [2]

**Any additional context**
not reproducible on Pixel