Intro Skipper doesn't work correct sometimes

I know it is not an official plugin but I hope someone can still help. In some cases I can see that when I use the intro skipper that it does skip for example to 1 minute 30 seconds and so correctly recognized the intro but instantly jumps to 1 minute. It is something you can only notice when you see the timebar. Without ot it just seems like it doesn't recognozid it correctly and only jumped to 1 minute. Something that also is strange is that it worked in case of Naruto when I still had the old episodes but when I switched them out for the blueray version the problem appeared. I am on version 10.10.7.