Hello everyone, newbie here so hopefully this query is not too idiotic...

I'm a pro guitar player and I'm gearing up for live streaming. There are a couple of issues around audio, however, that can come later. The first problem is I'm getting a lag between what is being recorded by my DSLR and actually seeing it on the preview within VMix of probably a quarter of a second. Should I expect this delay and just get on with it? It's not a lot, but it really is a nightmare when recording with acoustic guitar. I can hear the guitar echo from what I play to it then being played a little while later. Also, it's annoying to see that I'm slightly out of sync with the preview.

The odd thing is that the preview of the camera in Streamlabs OBS is almost bang on (but not quite).

Here is my equipment for reference...

Canon 700D
Mirabox capture card
Dell T7500 - 2 x 5690 chips, 48 Meg ram, SSD, Nvidia K4200
Windows 10
USB 3.0 available and used

I'd like to see if I can fix this as vMix seems to be what I would want specifically from an audio integration point of view.

Thanks for any advice or help in advance.

Ged