Hello, I’ve got a 2009 Mazda 3 Bose sound system I just bought. I didn’t really like the aftermarket stereo that the previous owned had installed (mostly because of the display for the climate control being missing). So I ordered a used factory radio off of eBay out of a junkyard. Looks great and I went on installing it. The factory radio that I’m installing works on everything except for putting sound out of the speakers. I emailed the company I bought it from and they told me that they tested it prior to removing it from the old car. I plugged back in the aftermarket stereo and everything works. Any ideas why this factory radio wouldn’t be putting out sound? Is it possible that they bypassed the factory amp maybe? I’m just kinda throwing out ideas because I don’t really know. Any help would be much appreciated.