Can't offer a job... but last summer I went through 10 interviews before I found my work-term placement. It was frustrating, so I know exactly what you're going through.
Advice - sit down and write down a few things from each interview you think went well, and if there was anything you think didn't go well. See if anything matches up, maybe it can give you a hint of things you could do better on the next opportunity. Also some people are willing to give feedback, it's one of those things you have to play by ear, but one of my interviews I made it to round 3 which was a dinner meeting with the owners, and I asked, what it was about me that got me in the door, so that I knew even if I didn't get the job I knew what I could work on to get the next one.
Good luck, I'm sure you'll find a great job, sometimes it just takes patience (I know not what you want to hear
)