IIRC, MDLive had some folks questioning the repeat tables issue, and they used the Bravo system to "randomly" select.
Since we are only hearing of "that time it repeated" I can't posit whether what is happening is within the realm of mathematical reason. It sure does sound like back-back repeats are quite common, but that might be "normal." If someone has that data, they can see if the random generator is behaving like it's supposed to.
Assume 8 draws/day.
If the draw is among 10 tables, then on any given draw there's a 10% chance of repeating the last draw, or a 90% chance of no repeat. Each of those chances are independent, and there's 7 chances a day.
Thus, the odds of no repeat are (.90^7) = 48%. So, for a given day, there's a 52% chance of (at least 1) repeat!
For 20 tables: 30%
For 30 tables: 21%
For 40 tables: 16% of days will have a back-back draw hit.
I'm not smart enough to do the 3-peat case