diff --git a/miniaudio.h b/miniaudio.h
index 0fd5c51c..f84e1298 100644
--- a/miniaudio.h
+++ b/miniaudio.h
@@ -62865,7 +62865,7 @@ static ma_result ma_decoder_seek_bytes(ma_decoder* pDecoder, ma_int64 byteOffset
 {
     MA_ASSERT(pDecoder != NULL);
 
-    if (pDecoder->onSeek != NULL) {
+    if (pDecoder->onSeek == NULL) {
         return MA_NOT_IMPLEMENTED;
     }