diff --git a/src/utils/buffer-helper.ts b/src/utils/buffer-helper.ts
index f656c8eb66b..415528adc51 100644
--- a/src/utils/buffer-helper.ts
+++ b/src/utils/buffer-helper.ts
@@ -91,6 +91,7 @@ export class BufferHelper {
     end: number;
     nextStart?: number;
   } {
+    pos = Math.max(0, pos);
     // sort on buffer.start/smaller end (IE does not always return sorted buffered range)
     buffered.sort(function (a, b) {
       const diff = a.start - b.start;