diff --git a/vav2/platforms/android/applications/vav2player/app/src/main/cpp/yuv_fragment.glsl b/vav2/platforms/android/applications/vav2player/app/src/main/cpp/yuv_fragment.glsl
index 2040fba..fa12588 100644
--- a/vav2/platforms/android/applications/vav2player/app/src/main/cpp/yuv_fragment.glsl
+++ b/vav2/platforms/android/applications/vav2player/app/src/main/cpp/yuv_fragment.glsl
@@ -13,6 +13,30 @@ void main() {
     // and the YCbCr conversion parameters from AHardwareBuffer format properties
     vec4 rgba = texture(ycbcrTexture, fragTexCoord);
 
-    // Output RGB color with full alpha
+    // DEBUG: Test if YCbCr conversion is actually happening
+    // If conversion works: rgba should be RGB (red sky = high R, low G, low B)
+    // If conversion FAILS: rgba will be YUV (Y in .r, U in .g, V in .b)
+    //   - For red pixels: Y=high, U=low, V=high -> would show as purple/magenta!
+
+    // DEBUG TEST 1: Show Y channel only (should show grayscale brightness)
+    // If this shows correct brightness, Y is in the right place
+    // outColor = vec4(rgba.r, rgba.r, rgba.r, 1.0);
+
+    // DEBUG TEST 2: Show U channel only (should show blue-yellow gradient)
+    // outColor = vec4(rgba.g, rgba.g, rgba.g, 1.0);
+
+    // DEBUG TEST 3: Show V channel only (should show red-green gradient)
+    // outColor = vec4(rgba.b, rgba.b, rgba.b, 1.0);
+
+    // DEBUG TEST 4: Try swapped UV (maybe U and V are reversed in NV12?)
+    // float Y = rgba.r - 0.0625;
+    // float V = rgba.g - 0.5;  // SWAPPED: V from .g
+    // float U = rgba.b - 0.5;  // SWAPPED: U from .b
+    // float R = Y + 1.5748 * V;
+    // float G = Y - 0.1873 * U - 0.4681 * V;
+    // float B = Y + 1.8556 * U;
+    // outColor = vec4(R, G, B, 1.0);
+
+    // DEBUG TEST 5: Raw passthrough (see what hardware gives us)
     outColor = vec4(rgba.rgb, 1.0);
 }
\ No newline at end of file
diff --git a/vav2/platforms/windows/vavcore/src/Decoder/MediaCodecSurfaceManager.cpp b/vav2/platforms/windows/vavcore/src/Decoder/MediaCodecSurfaceManager.cpp
index 487d2bd..ac49980 100644
--- a/vav2/platforms/windows/vavcore/src/Decoder/MediaCodecSurfaceManager.cpp
+++ b/vav2/platforms/windows/vavcore/src/Decoder/MediaCodecSurfaceManager.cpp
@@ -365,25 +365,45 @@ bool MediaCodecSurfaceManager::CreateVulkanImage(void* vk_device, void* vk_insta
     LogInfo("  is_qualcomm_gpu (Adreno): " + std::string(is_qualcomm_gpu ? "true" : "false"));
     LogInfo("  is_samsung: " + std::string(is_samsung ? "true" : "false"));
 
+    // CRITICAL: For external formats (Qualcomm vendor formats), we MUST attach VkExternalFormatANDROID
+    VkExternalFormatANDROID externalFormat = {};
+    externalFormat.sType = VK_STRUCTURE_TYPE_EXTERNAL_FORMAT_ANDROID;
+    externalFormat.pNext = nullptr;
+    externalFormat.externalFormat = 0;  // Will be set if using external format
+
     VkSamplerYcbcrConversionCreateInfo ycbcrConversionCreateInfo = {};
     ycbcrConversionCreateInfo.sType = VK_STRUCTURE_TYPE_SAMPLER_YCBCR_CONVERSION_CREATE_INFO;
-    ycbcrConversionCreateInfo.pNext = nullptr;
+    ycbcrConversionCreateInfo.pNext = nullptr;  // Will chain externalFormat if needed
 
-    // Use format properties from AHardwareBuffer
+    // CRITICAL FIX: Use AHardwareBuffer's actual format, NOT Vulkan's suggested format!
+    // Qualcomm returns VK_FORMAT_UNDEFINED (0) in ahb_format_props.format
+    // But the REAL format is in ahb_desc.format (Qualcomm vendor format 0x7FA30C04)
+    //
+    // We need to use the AHardwareBuffer format directly as a Vulkan "external format"
     VkFormat vulkan_format = ahb_format_props.format;
+
+    // Log both formats to debug
+    LogInfo("Format detection:");
+    LogInfo("  AHardwareBuffer format (ahb_desc.format): 0x" + std::to_string(ahb_desc.format));
+    LogInfo("  Vulkan suggested format (ahb_format_props.format): " + std::to_string(ahb_format_props.format));
+
     if (vulkan_format == VK_FORMAT_UNDEFINED || vulkan_format == 0) {
-        // WORKAROUND: GPU-specific format detection
-        // Qualcomm Adreno GPU → NV21 (CrCb) requires component swizzle
-        // Other GPUs → NV12 (CbCr) standard format
-        if (is_qualcomm_gpu || is_nv21_device) {
-            vulkan_format = VK_FORMAT_G8_B8R8_2PLANE_420_UNORM_KHR;  // NV12 format (will use BT.601)
-            is_nv21_device = true;
-            LogInfo("Qualcomm Adreno GPU detected → Using NV12 format with BT.601 + component swizzle");
-        } else {
-            vulkan_format = VK_FORMAT_G8_B8R8_2PLANE_420_UNORM_KHR;  // NV12 format
-            is_nv21_device = false;
-            LogInfo("Non-Qualcomm GPU → Using NV12 format with MediaCodec settings");
-        }
+        // CRITICAL: Qualcomm GPU returns UNDEFINED format
+        // We MUST use external format instead of hardcoding NV12!
+        LogInfo("Vulkan driver returned VK_FORMAT_UNDEFINED - using external format path");
+        LogInfo("  This is EXPECTED on Qualcomm Adreno GPUs with vendor-specific formats");
+
+        // Use the AHardwareBuffer's native format as external format
+        externalFormat.externalFormat = ahb_desc.format;  // 0x7FA30C04 for Qualcomm
+        ycbcrConversionCreateInfo.pNext = &externalFormat;  // Chain external format
+        vulkan_format = VK_FORMAT_UNDEFINED;  // MUST be UNDEFINED when using external format
+
+        LogInfo("Using external format:");
+        LogInfo("  externalFormat = 0x" + std::to_string(externalFormat.externalFormat));
+        LogInfo("  Vulkan format = VK_FORMAT_UNDEFINED (required for external formats)");
+    } else {
+        LogInfo("Vulkan driver provided explicit format: " + std::to_string(vulkan_format));
+        LogInfo("  NOT using external format path");
     }
 
     ycbcrConversionCreateInfo.format = vulkan_format;
@@ -447,20 +467,40 @@ bool MediaCodecSurfaceManager::CreateVulkanImage(void* vk_device, void* vk_insta
     external_mem_info.sType = VK_STRUCTURE_TYPE_EXTERNAL_MEMORY_IMAGE_CREATE_INFO;
     external_mem_info.handleTypes = VK_EXTERNAL_MEMORY_HANDLE_TYPE_ANDROID_HARDWARE_BUFFER_BIT_ANDROID;
 
+    // CRITICAL: For external formats, chain VkExternalFormatANDROID to VkImageCreateInfo
+    if (vulkan_format == VK_FORMAT_UNDEFINED) {
+        external_mem_info.pNext = &externalFormat;  // Chain external format
+        LogInfo("VkImage: Chaining VkExternalFormatANDROID (format=0x" + std::to_string(externalFormat.externalFormat) + ")");
+    } else {
+        external_mem_info.pNext = nullptr;
+        LogInfo("VkImage: Using explicit Vulkan format (no external format)");
+    }
+
     VkImageCreateInfo image_info = {};
     image_info.sType = VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO;
     image_info.pNext = &external_mem_info;
+    image_info.flags = 0;  // CRITICAL: Must be 0 for external formats
     image_info.imageType = VK_IMAGE_TYPE_2D;
     // Use the same format as YCbCr conversion (already validated above)
     image_info.format = vulkan_format;
     image_info.extent.width = ahb_desc.width;
     image_info.extent.height = ahb_desc.height;
     image_info.extent.depth = 1;
-    image_info.mipLevels = 1;
-    image_info.arrayLayers = 1;
-    image_info.samples = VK_SAMPLE_COUNT_1_BIT;
+    image_info.mipLevels = 1;  // CRITICAL: Must be 1 for external formats
+    image_info.arrayLayers = 1;  // CRITICAL: Must be 1 for external formats
+    image_info.samples = VK_SAMPLE_COUNT_1_BIT;  // CRITICAL: Must be 1 for external formats
     image_info.tiling = VK_IMAGE_TILING_OPTIMAL;
-    image_info.usage = VK_IMAGE_USAGE_SAMPLED_BIT | VK_IMAGE_USAGE_TRANSFER_DST_BIT;
+
+    // CRITICAL: External formats ONLY support VK_IMAGE_USAGE_SAMPLED_BIT
+    // Adding TRANSFER_DST causes crash on Qualcomm GPUs
+    if (vulkan_format == VK_FORMAT_UNDEFINED) {
+        image_info.usage = VK_IMAGE_USAGE_SAMPLED_BIT;  // ONLY sampled for external formats
+        LogInfo("VkImage: usage = SAMPLED_BIT only (external format restriction)");
+    } else {
+        image_info.usage = VK_IMAGE_USAGE_SAMPLED_BIT | VK_IMAGE_USAGE_TRANSFER_DST_BIT;
+        LogInfo("VkImage: usage = SAMPLED_BIT | TRANSFER_DST_BIT");
+    }
+
     image_info.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
     image_info.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;