String Trimmers

I bought a 128ld split shaft trimmer, and I'm beginning to regret it. First of all it was very difficult to start. The first time I used the trimmer it seemed to be "bogged" down the whole time, eventually it did seem to run at full throttle but still seemed it wasn't running correctly. Also it will not idle at all. The next time I cranked it (about 2 hours later) it would never run at full throttle, it would barely turn the trimmer head. It feels like it's not getting enough fuel, I tried to manually open the throttle more at the carburetor but it seemed that it was open. I don't know if this helps, but if I pumped the primer bulb while it was running, then it would get to full throttle for a couple of seconds bu then bog back down. My fuel mixture is good, I was also running another husqvarna trimmer and a stihl trimmer with the same mixture with no problems. I am not a small engine mechanic so I could easily be overlooking something, but I do own a few string trimmers and am familiar with the basics, any help would be appreciated.