I am using Memorex CD-R 700mb and have found that they play fine when written from my sony dru-500a. However, they do not play or only sometimes play when written with a Samsung SW-240B on my other PC. Any ideas why this is? Is it possible that the record speed has any thing to do with this? I am using Nero Burning ROM on both setups and have also tried EZ CD Creator. What could the problem be? I am attempting to play them in a car stereo.