Thanks so much for the reply, I really hope I can fix this issue as nothing seems to work !! My Swift model is Swift SF314-42, and I am using Windows 10. I am hoping that my choice of decks (Numark NS4FX) is compatible with this model.. it's a fairly new laptop, so I don't see why it wouldn't be?

As requested, my device manager snap is below. With nothing expanded, were you looking for any caution signs? As you can see, there are none.

I thought about it being a firmware issue, but there is no option for any firmware with this particular device through Numark at time of writing.

In terms of Serato, Serato Pro is convinced everything is working fine, and even says, 'Numark NS4FX connected'. There just is no sound - when my decks are connected. The sound is fine when there are no DJ decks attached, which is odd, so surely this is a config issue.

Also an update on the bitrate, I spent some time downloading and installing Realtek High Definition Audio, and get to choose between 48k, 96k, or 192k Hz.. strange as I could change this to 24 bits yesterday after the driver change, but today it's reverted back to the 16 bit config (apparently the human ear can't detect the difference anyway?). In short, no difference based on bit rate (leaving the Hz at 48 as advised by Numark).

Numark suggested it's a hardware issue, to try a different computer etc., so I might look into this, although I'm not wholly convinced it's just a hardware issue. It seems like a soundcard issue, and I gave a detailed walkthrough to them about each step of my troubleshooting over three levels, which I've reproduced below if this helps.

1. In general Windows Settings (controller as output device, laptop soundcard as input):

(troubleshooter is no good).

2. in advanced sound settings (controller as output when using Serato DJ Pro):

3. 'Additional device properties' in general settings, under the 'Listen' tab I said to playback through the controller.

No luck though. This is my first time trying to get any music tech to speak with my laptop, so this may be a newbie thing, but how does the interface actually work, between machine and device in terms of sound card and the configuration of each? Apparently the NS4FX needs to be the output, but I'm still a bit stumped as doesn't this come from the laptop, or Serato first, anyway? On Serato btw there is also a handy option, 'Use Laptop Speakers', so the sound goes out to the device then back to the laptop thru the software? I selected this, but it makes absolutely no difference anyway.

Unfortunately, the problem persists, which is why I came to these forums to see if it was an issue with my laptop hardware, before looking into the Numark hardware. Any suggestions or ideas? Would be most welcome, as I've spend hours and hours pursuing this to no avail thus far.

I have a screenshare with Numark next week, although they said according to info above / at least software windows config-wise, everything seems fine.

Thanks in advance! Happy to provide any further info.

success at last! Finally managed to get my NSF4X to play nicely with my Swift, and get sound through laptop speakers - thanks so much for the help. Finally answers my question if it's a laptop hardware issue, and the result was no, it was just a sound config issue.

It seems like there's a wealth of DJ experience here though so was wondering if any one had any tips on using headphones with hardware and Serato? I plugged these into my decks, although seemed to have a problem separating the cue mix from the main mix.

Ideally I'd like the cue mix through my headphones only, and the main mix through the assigned sound output - in this case laptop speakers, but maybe external speakers later.

The main point being I should be able to listen to the cue mix without this playing at the same time as the main song.. on both headphones and speakers? .. I'd like to prepare the cue track using headphones, work and warp the main track (without the cue output being disturbed), and then blend the cue in with the main at the right moment. Is this a workflow thing ? It doesn't seem like the crossfader does a lot here, which was surprising - but even then is that adjusting output for headphones or for the external output?

Is it common practice to adjust filters, so that the cue and main song play differently?? Bit confused here as this worked a little but still had the same problems of both songs merging into a single audio output. Would be ideal to have them separate.

Thanks for help all, the inline replies are a bit disordered so I'll reply in order below to these:

@ Joe9844, in response to your 1), yes, messing with the audio drivers very much did screw up the audio!
I did a restore though and this seems to have helped. Weird how dependent the OS is on a driver or too, I thought it would be more resilient than that.

2) I'm not sure about 'nobody', but I wanted to practice on my laptop .. as well as rely less on even extra hardware.
I did get the laptop speakers to work in the end (different machine) - couldn't hear any latency.

@ JackE: As I mentioned, my decks are Numark NSF4X. To update, these actually worked ok on a different machine. Thing is, that machine is older, and I'd rather not DJ on it. It is Intel though - my main Acer Swift is Ryzen.

Which brings me to the laptop hardware and why I'm here - is it that Ryzen / Numark NSF4X don't mix ? I will try to config further on my Swift, seeing that they work on my older Intel, but am a bit exhausted from troubleshooting so will see if works later.

@ Joe 9844, thanks for the link; Serato support forwarded me to the same article.

Funnily enough, the whole soundcard config thing needs to be the laptop soundcard, NOT the device, IF using laptop speakers.

Will try this out later.

Any techy / processor thoughts would be good, also to see if I can purchase any hardware for my Acer to address this? Maybe another processor, or a different processor? Would be interesting to find the cause of the whole problem, especially now it works on my Intel laptop.

thanks for help so far all.