Yep. Time to replace it for $20 to $25. They are not worth the troubles of trying to fix them. They wear out too fast when often used... Avoid Sony, Sony Nec, Asus, HP, Memorex, LaCie, Acer.
Consider LG, Samsung, Pioneer, LiteOn. Plextor and Yamaha are the most reliable, but expensive, when you can find them.