i was having the same problem until i took  it out and cleaned the disc but i didnt have the problem till i downloaded the new update and/or the terminal map

never had this problem untill the latest patch... now its every other match i play on team defender, freezing and giving the disc read error

This seemed to fix my disk error problem

From the ps3 menu,

2. Select Internet Browser.

3. After the Internet Browser appears press the Triangle button.

4. Select Tools on the Options menu.

5. Select Delete Cookies and Delete Cache

6. delete game data utility for MW3 (witch is the update)

7. reinstall update and it should work.

You have been hacked or infected by someone. Try making a new psn account on your ps3 until the virus is gone.This happend to me and  i did this and waited 5 days and it worked.

-Ac130 don't give me kills,Pavelow gets shotdown,Semiwolf on a Reaper is all I need!

I started having this issue a few days ago. I've had my copy since the midnight release and no issues up till this point.  Tried the whole unistall update, install game(360) step by step and it didn't seem to work for me. I did notice however that it began after I downloaded the Collection 4 maps. I was going to try just deleting all the maps I downloaded, but noticed that a lot of the spec ops maps were 100mb+ so I deleted those, cleared cache in my HDD, and now I'm back in business. I don't play spec ops missions anyways, so it wasn't a big lost for me. If you guys are still have the same issue, I would go ahead and give that a try as well if you haven't.