Preamp Recommendations?

I have n-track 8 and Windows 10 on a laptop. I’m looking for recommendations for a preamp just so I can play back tracks and monitor the new track I’m recording at the same time. This seems like it should be very straightforward, but I have really fought with the FastTrack Ultra that I have. After tons of struggle, I managed to get it to work once, but I can’t replicate it. Either I can hear the playback or I can monitor what I’m recording, but not both. I don’t need more than one input on the preamp. It can be cheap. I just want to multitrack without lag!