I have searched TechSpot and the Internet, and haven't been able to find an answer to this problem. When I tried to play a dvd on my laptop, picture and sound was stuttering. This has never happened before. The dvd drive plays audio cds without any problems, but all the dvds I tried had stuttering. When I checked "control panel/hardware/device manager/ide ata atapi controllers" I found that the secondary ide channel was missing. It used to be there. Do I have a hardware problem (dvd driver or motherboard)? The laptop is an Acer with a Mobile Intel Pentium M 760J, 2000 MHz (15 x 133) and a PIONEER DVD-RW DVR-K16RA. I have klmcodec installed, and the dvd plays without any problems on my other computer. Thanks in advance for any help and advice.