diff --git a/media/libeffects/visualizer/EffectVisualizer.cpp b/media/libeffects/visualizer/EffectVisualizer.cpp
index e7eccf1..96935e3 100644
--- a/media/libeffects/visualizer/EffectVisualizer.cpp
+++ b/media/libeffects/visualizer/EffectVisualizer.cpp
@@ -61,7 +61,7 @@
     uint32_t mCaptureSize;
     uint32_t mScalingMode;
     uint8_t mState;
-    uint8_t mLastCaptureIdx;
+    uint32_t mLastCaptureIdx;
     uint32_t mLatency;
     struct timespec mBufferUpdateTime;
     uint8_t mCaptureBuf[CAPTURE_BUF_SIZE];
@@ -499,7 +499,7 @@
                 memcpy(pReplyData,
                        pContext->mCaptureBuf + CAPTURE_BUF_SIZE + capturePoint,
                        size);
-                pReplyData += size;
+                pReplyData = (char *)pReplyData + size;
                 captureSize -= size;
                 capturePoint = 0;
             }