diff --git a/dom/media/webm/WebMReader.cpp b/dom/media/webm/WebMReader.cpp
index 6a96a8772f24..5ae7e335cf2c 100644
--- a/dom/media/webm/WebMReader.cpp
+++ b/dom/media/webm/WebMReader.cpp
@@ -750,8 +750,16 @@ nsresult WebMReader::SeekInternal(int64_t aTarget)
   uint64_t target = aTarget * NS_PER_USEC;
 
   if (mSeekPreroll) {
-    target = std::max(uint64_t(StartTime() * NS_PER_USEC),
-                      target - mSeekPreroll);
+    uint64_t startTime = uint64_t(StartTime()) * NS_PER_USEC;
+    if (target < mSeekPreroll || target - mSeekPreroll < startTime) {
+      target = startTime;
+    } else {
+      target -= mSeekPreroll;
+    }
+    LOG(LogLevel::Debug,
+        ("Reader [%p] SeekPreroll: %f StartTime: %f AdjustedTarget: %f",
+        this, double(mSeekPreroll) / NS_PER_S,
+        double(startTime) / NS_PER_S, double(target) / NS_PER_S));
   }
   int r = nestegg_track_seek(mContext, trackToSeek, target);
   if (r != 0) {