Yes, I have just bought the product, I have a Macbook software latest version in March 2019. I have requested help but none offered so far. I have the same problem, the recording just stops after a few seconds. On closing Sound Tap, the music continues as before.....
I see that at least two other people have the same problem with no help from the technical people. After paying for a product, it should, simply, work!
I will give it another couple of days then if no help offered, I will stop the credit card payment;