Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Issues

I received one of these as a gift a few years ago, and liked the product. Finding it very functional, I decided to purchase 2 more. There were quality control issues with the 2 units I recently received. One plug-in receiver unit didn't work at all. The plastic on the jumpers used in the plug-in receivers and remote control transmitters, on both units fell apart when resetting the codes (strange). I replaced them with my own jumpers. I didn't bother to return the one defective unit, because I was able to use the transmitter as an extra.