How do i use set speed to burn?

I use NeroUpdateDeviceInfo to update the speed of DVD.for example:nsiNumSupportedSpeeds = 8.after this function is excuted,I examine to the results.the results:3,9,18,22.
nsiNumSupportedSpeeds:3
nsiSupportedSpeeds:9,18,22.
how do i do?thanks a lot!!! :sad:

What exactly is the problem?

If the speeds you get are not precise enough for you, there is also a nsiSupportedSpeedsKBs array. If you divide the speeds in this array with nsiBaseSpeedKBs you may even get fractional speeds such as 2.4x which is not uncommon with DVDs.