can you send me a link to your sitemap?
visiting https://www.broadbandtalk.in/t…ple-iphone-5-apple-ipad3/ (the moddate for that is <lastmod>1969-12-31T16:00:00-08:00</lastmod>) yields to an error.
edit: Any link that has a `lastmod` of the last century yields to an Error.
Well, perhaps a case of threads without posts?! Have you checked if any of those threads does actually have posts?
You might want to check if there are any threads without posts in the database. A sql of this sort might be handy.SQL
If this query yields any results compare them to the threads with wrong dates in your sitemap. They might match...