Macworld If you own a recent iPhone before the latest model, two things are true: It has a Lightning port and it doesn’t have a headphone jack. Today’s deal can fix that for very cheap: Best Buy is selling a 2-pack of Insignia Lightning to 3.5 mm Headphone adapters for just $6, a savings of $11.50 and the best price you’re ever going to see. This adapter has one job: One end connects to the Lightning port on your iPhone and the other accepts a 3.5mm jack from your headphones or some other audio device. The cables are braided, so they should stay free from frays and breaks, and since you get tw…