I know this is a bit of an old thread but for anyone who comes across it this is what I did to help the recordings sound better:
–Go through each track and gain it (not the master gain, gain on each track). Gain it until the loudest part is within the ~top yellow (make test recordings and try them on other stereos to dertermine what you think sounds best). Trial and error is valuable.
–Ensure auto gain is on in serato, default is 92db. IT should come on when you open serato, mine always resets if Serato is closed.
–On my DDJSR, I am finding the trim needs to be around 8-9 depending on the track. Find a good balance between trim and the gain.
–Jet audio is a cool free program that will burn CDs, and convert to als, wav, ogg, mp3, etc. and it runs very well on Windows 10. It will also normalize an audio file if needed.
–Free Wav converter is a really tiny no bloat free software that just does basic wav editing and MP3 conversion.
Another random comment: My laptop runs Serato much better when I run it from the GPU. This is not possible though unless you have a dedicated GPU (alienware laptops, etc.). Its just much smoother and has never crashed. This is purely based on personal observation.
Hope my experiences help someone.