Gray background won't print solid, help please

I'm trying to print a picture of old bottles that I photographed on a light gray background, I'm running Photoshop CC.(did not see a forum for that here). Anway, the bottles print fine, but my background won't print solid. I get a wide gray streak and then a wide white streak repeated across the page, not solid gray. I'm printing on a Canon laser printer. Can anyone help me, I've tried many different settings but nothing works. The machine isn't dirty, other pictures print fine that don't have a gray background. I also have a new toner cartridge. Thanks.