I'm where you are right now; I like my boss but I don't like the job, and instead of using my talents they are keeping me chained to a sales desk where I cringe

I'm where you are right now; I like my boss but I don't like the job, and instead of using my talents they are keeping me chained to a sales desk where I cringe every time a sales call comes in. I do my job and do it well, but I could be a much greater asset if they would use me for what they hired me for. So, I'm looking for another job and my boss knows it. Now, he's having me train other existing employees to do my IT and repair duties as they have time, and is planning on hiring another salesperson. It's my personal opinion that the owner is being cheap; we recently lost our lead sales rep and that's why I got chucked into that role. The rep who left was making three times what I am (he had been with the company for 20+ years) but instead of hiring a replacement at base pay or raising my pay to a level where I could accept the extra duties, he is cheaping out. Now, he's losing me because of it and he admits that he regrets it. So, I say if they refuse to use your real talents and pay you what you're worth, it's definitely time to move on.