Good morning I'm sorry to hear about that.
Standard speakers should work fine on this unit.
It sounds like you may have a defective unit. But just to be sure you should try a different set of speakers. If you don't have one available you could purchase a cheap set from like a discount store or even Walmart.
But the Sylvaniaa unit should still be fully covered under the warrant so you can exchange that one as this one is most likely defective;-(
I wish I had better news for you on that I really do.
In any case, I will stick with you until this is complete.
Please rate kindly thus far, it won't cost you anything to rate my service to you kindly,
Then you can reach me by simply replying to this message anytime.
Thank you and have a nice day!