Yes that‘s right.
Lets say you‘ve created a pattern with different instruments. Everything works as expected. Then you go to sample Editor and change some settings for a sample. When you go back to pattern page the tracker doesn’t make any sound anymore.
Unfortunately I can‘t tell you the exact steps to reproduce this behaviour. I use the tracker a lot and this only happened 2 or 3 times now. I can’t exactly remember what I did in the sample editor.