fix android auto quirks

modules/astra-scope/android/build.gradle

@@ -33,3 +33,7 @@ android {
     abortOnError false
   }
 }
+
+dependencies {
+  testImplementation 'junit:junit:4.13.2'
+}

modules/astra-scope/android/src/main/java/expo/modules/astrascope/AstraScopeModule.kt

@@ -79,6 +79,12 @@ class AstraScopeModule : Module() {
       GainBridge.activateSmoothFor(url)
     }
 
+    // Hard-prime while paused; unlike activateTrackGain this must not spend the
+    // first audible second gliding down from the process default (unity).
+    Function("primeTrackGain") { url: String ->
+      GainBridge.primeFor(url)
+    }
+
     // Conservative temp gain applied when a transition hits an unregistered URL
     // (unanalyzed track). JS keeps this at 1 while normalization is disabled.
     Function("setFallbackGain") { linear: Double ->

modules/astra-scope/android/src/main/java/expo/modules/astrascope/GainBridge.kt

@@ -89,6 +89,15 @@ object GainBridge {
     setTarget(gains[url] ?: fallbackGain, CORRECTION_RAMP_MS)
   }
 
+  /**
+   * Prime a paused player before play is released. There is no live signal to
+   * declick here, so publishing a zero-duration target guarantees the first
+   * processed frame is already at the requested gain.
+   */
+  fun primeFor(url: String) {
+    setTarget(gains[url] ?: fallbackGain, 0)
+  }
+
   /** Glide to an explicit gain (unity paths: no track / remote track / disabled). */
   fun setGainSmooth(linear: Float) {
     setTarget(linear, CORRECTION_RAMP_MS)

modules/astra-scope/android/src/test/java/expo/modules/astrascope/GainBridgeTest.kt

@@ -0,0 +1,26 @@
+package expo.modules.astrascope
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class GainBridgeTest {
+  @Test
+  fun pausedPrimePublishesTargetWithoutCorrectionRamp() {
+    GainBridge.putGain("test-track", 0.25f)
+
+    GainBridge.primeFor("test-track")
+
+    assertEquals(0.25f, GainBridge.targetGain, 0.0001f)
+    assertEquals(0, GainBridge.rampMs)
+  }
+
+  @Test
+  fun pausedPrimeUsesFallbackForUnanalyzedTrack() {
+    GainBridge.fallbackGain = 0.5f
+
+    GainBridge.primeFor("missing-track")
+
+    assertEquals(0.5f, GainBridge.targetGain, 0.0001f)
+    assertEquals(0, GainBridge.rampMs)
+  }
+}