jonny12345 wrote:3)when you go into preferences and click on audio, it has things called 'hz' e.g '44100 hz' '48000 hz' what does this mean?
Hz = Hertz = frequency-measurement (e.g. how often does something vibrate o.s. per second)
in this case it means how often per second (44100 or 48000 times)
the Audio signal is read. (aka Samplerate)
To understand this you must know the difference between analog and digital signal (which i really cant explain loosing myself in 10 other things that are relevant)
To you as a DJ basically 2 things are important to know.
1: CD (aswell as most download material) is recorded as 16-bit/44100Hz, as this is digital-audio there is no natural waveform to the signal, but very, very small peaks combined to a waveform (kinda like when you try to determine the space under a curve in math) this also means that samplerate other than 44100Hz and multiples of 44100Hz might lead to failure in the audio, as the peaks might not be read correctly anymore.
e.g you use 96000Hz and the ausio is 44100Hz there will be peaks read where only one should be, but actually there are two, whereas when you use 88200Khz on 44100Khz the problem wont exist as it a natural multiple.
2: using an Soundcard/interface the samplerate also determines how fast it works (-> using 88200Hz instead of 44100Hz will half the time the interface needs to process a certain amount of data, therfor it will feel more direct to the point where you cant feel a difference to an analog source (=vinyl) anymore, which is especially important when scratching etc.
is the measurement of sound levels,,,all music is not at the same sound levels the same two songs/tracks for what ever reason, can have different sound levels.this is a way to adjust the levels so they can be the same 
if you look in the info panel you can adjust the gain levels to o by changing the value there, also you can select all and edit all to o , i have had no sucess with this , 
the other end is that the adjustment prevents saturation and distortation 
,,just went from 3 to 6 in the past updates, and was able to give some input to the choices 
