@ngm
Sounds like caching is involved. https://www.metabase.com/docs/latest/administration-guide/14-caching.html
But check your database query log, so you can see exactly what and when it receives queries.
If you say that it happens consistently, then you should be able to reproduce, which will help narrowing down where the problem is. The more simple and into the core the reproduction is, the easier it would be to figure out what the problem is.
Sounds similar to Query result issue, though that seemed it happened across just a simple question.