My only guess is that you have a large database and an inefficient query causing the issue. I'd have to see the page causing the problem and possibly have access to the database to debug. The issue isn't with the rsobj.php file itself. It is probably an issue with inefficient recordsets.
You could try changing this line in the rsobj.php file:
$this->Prepared = true;
$this->Prepared = false;
That would improve efficiency, but I generally don't recommend trying to change code to fix a problem until you have isolated it and fully understand the issue at hand.