I have tried the USA Spec unit on my 05 4runner limited with JBL and had issues. It would work great for about 10 minutes then would cut out and become non-existent to the stereo until the key was turned off, then back on. I called tech support several times and they were not able to help me figure out the issue. They told me to removed my stereo and send it to them and if they had time they would look into it. I returned the USA SPEC unit and ended up trying the GROM BT unit and it works flawlessly. I wish I would have tried that first and saved myself some aggravation.