The problem is most likey your disc drive. I had one of the original xbox's and had the very same issue. They started out using Thompson, then switched to Philips, then switched to Samsung. They did this because of all the issues their customers were experiencing. You can tell which one you have by the ejecting the dvd drive and looking at it. Here are pictures of the three:
You can purchase replacement drives on ebay for really cheap and swap it out yourself easily. Here is an example of an auction on ebay of the drive for sale and the example is of the Samsung drive:
Hope this helps.
There is soo many ways to answer this. Have the discs ben damaged ? is the dvd player lens dirty ? the best way is to get a cd lenz cleaner cd, use it to clean the dvd player, if this dosent sort the problem look at the games u are trying to play if they are scratched bad.. then its probably the game..if not then the dvd could be faulty and the easiest solution is to buy another unit secondhand as they as cheap as chips !!
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