I’ll tell you, once upon a time when my family used to watch a lot of DVDs & Blu-Ray discs we actually had 2 different players (a Sony & a Samsung) attached to the same TV. We used to get discs in the mail from Netflix (many of which were fairly battered), and sometimes a disc would be glitchy in one player but run fine in the other, and vice-versa. The fact, though, that you’re saying that multiple pristine discs are playing poorly in this player doesn’t sound right. I’d return the thing and get something a bit higher end. And by “higher end,” I’m not talking about a fortune. The “higher end” players might be $30-$50 more than you paid... which is like the cost of a couple pizzas.
I have my receipt, so that may be the simplest solution.