Audio Failure During Playback

For some reason, I’m having this odd issue where the audio of a synth I created is not showing up in playback. Anytime I would change the preset, it would fail. Every time I would change the audio device, it would fail. And if I tried to close the project and load it again, it would still not work. The only way I could get it to fix itself was by duplicating the track and then deleting the old one, which is not the most practical thing to do, surely, and I do not know why this is happening. I’d have a screenshot for you, but I have no idea where the problem’s source is, so I don’t know what to get a screenshot of. Does anyone know what I could do to potentially fix this? To clarify, I’m using Mixcraft 9 Pro Studio as my DAW.