diff --git a/tests/scraper_test.py b/tests/scraper_test.py
index b4c8cf4..395b759 100644
--- a/tests/scraper_test.py
+++ b/tests/scraper_test.py
@@ -135,4 +135,4 @@ def test_scrape_video_only2():
     with tempfile.TemporaryDirectory(dir="./") as tempdir:
         vks.download_media(res, tempdir)
         found_files = set(os.listdir(tempdir))
-        assert "video-17546758_456239898_0.mkv.webm" in found_files
+        assert "video-17546758_456239898_0.webm" in found_files
diff --git a/vk_url_scraper/scraper.py b/vk_url_scraper/scraper.py
index 234ab8b..33eeca6 100644
--- a/vk_url_scraper/scraper.py
+++ b/vk_url_scraper/scraper.py
@@ -312,7 +312,7 @@ class VkScraper:
                             downloaded.append(filename)
                 elif k == "video":
                     for i, url in enumerate(attachments):
-                        filename = os.path.join(destination, f"{r['id']}_{i}.mkv")
+                        filename = os.path.join(destination, f"{r['id']}_{i}.%(ext)s")
                         ydl = yt_dlp.YoutubeDL(
                             {
                                 "outtmpl": filename,
@@ -323,5 +323,12 @@ class VkScraper:
                         )
                         info = ydl.extract_info(url, download=True)
                         filename = ydl.prepare_filename(info)
+                        if "unknown_video" in filename:
+                            new_filename = filename.replace("unknown_video", "mkv")
+                            with open(filename, "rb") as vin, open(new_filename, "wb") as vout:
+                                vout.write(vin.read())
+                            os.remove(filename)
+                            filename = new_filename
+                        print(filename)
                         downloaded.append(filename)
         return downloaded