XBox 360 S - Unrecognized disc error/stuck on XBox screen

Hey folks, wondering if there's anyone out there who has any suggestions to help me get my XB360S disc drive working again. I bought this console off eBay, and the only issue I had was, it was not reading discs. Had the security sticker on it, and the plastic rivets were still in place on the end bezels. Overall, the console was fairly clean, and I cleaned everything, put new thermal paste on the GPU. The disc drive is a Hitachi-LG model. I tried replacing the laser itself (removed the anti-static solder ball), and am still getting the same problem where it can't read discs. I tried several different games and I either get "unrecognized disc", or it gets stuck on the XBox 360 logo when trying to load the game.