Help! cannot Alter Write Speed on HP DVD Re-Writer

[James]

Hi,
Before last week I was able to alter the write speed to my H.P. DVD
Re-Writer by using the properties and settings button on Windows Media
Player. I could set it to Fastest possible down to X1. Yesterday when
trying to burn and Audio CD this button was grayed out. I have also
adjusted it using properties on the drive itself in My Computer and
can no longer do this.
Any Ideas on what could be causing this problem. I also use Sonic
Record Now Software that came with my machine and this has never had
an option to alter the write speed.
Could this be a hardware problem ?

Thanks and Regards
James