diff --git a/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultAllocator.java b/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultAllocator.java
index d9bd5873f0..06ca83dd93 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultAllocator.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/DefaultAllocator.java
@@ -118,8 +118,18 @@ public final class DefaultAllocator implements Allocator {
     }
     for (Allocation allocation : allocations) {
       // Weak sanity check that the allocation probably originated from this pool.
-      Assertions.checkArgument(allocation.data == initialAllocationBlock
-          || allocation.data.length == individualAllocationSize);
+      if (allocation.data != initialAllocationBlock
+          && allocation.data.length != individualAllocationSize) {
+        throw new IllegalArgumentException(
+            "Unexpected allocation: "
+                + System.identityHashCode(allocation.data)
+                + ", "
+                + System.identityHashCode(initialAllocationBlock)
+                + ", "
+                + allocation.data.length
+                + ", "
+                + individualAllocationSize);
+      }
       availableAllocations[availableCount++] = allocation;
     }
     allocatedCount -= allocations.length;