diff --git a/strip_track_except.sh b/strip_track_except.sh
index 24f764f..539b0e3 100755
--- a/strip_track_except.sh
+++ b/strip_track_except.sh
@@ -10,5 +10,15 @@ FILENAME=$1
 LANGUAGE_TO_KEEP="${2:-jpn}"
 echo -n "Processing "
 colorprint "$FILENAME"
+
+# capture JSON output and remove the excessively large code_private_data field
+JSON_OUTPUT=$(mkvmerge -J "$FILENAME" | jq '[ .tracks[] | select(.type=="audio") | del(.properties.codec_private_data) ]')
+TRACK_COUNT=$(echo "$JSON_OUTPUT" | jq length)
+# check if more than 1 audio track is present
+[[ $TRACK_COUNT -lt 2 ]] && echo -e "\tFile has only 1 track, skipping." && exit 1
+# check if tracks other than the one to keep are present
+UNDESIRED_TRACK_COUNT=$(echo "$JSON_OUTPUT" | jq '[.[] | select(.properties.language!="$LANGUAGE_TO_KEEP")] | length')
+[[ $TRACK_COUNT -lt 2 ]] && echo -e "\tFile has only '$LANGUAGE_TO_KEEP' tracks, skipping." && exit 1
 FILENAME_WITHOUT_EXT=${FILENAME%.*}
-ffmpeg -i "$FILENAME" -map 0:v -map 0:a:m:language:${LANGUAGE_TO_KEEP} -map 0:s -c copy "${FILENAME_WITHOUT_EXT}.converted.mkv"
+echo -e "\tRemoving all audio tracks except '$LANGUAGE_TO_KEEP' tracks..."
+pv "$FILENAME" | ffmpeg -i pipe:0 -map 0:v -map 0:a:m:language:${LANGUAGE_TO_KEEP} -map 0:s -c copy -v warning "${FILENAME_WITHOUT_EXT}.converted.mkv"