Obbea Diva Shifting Problems

[MyOrbeaDiva07]

Help?! I have an Orbea Diva 07, with all Durace components. I put appx. 3K miles on it a year. I have a Compact Double with a 11/28 Shimano Cassette. I have been having shifting problems since I bought the bike in April 07. I need to have it adjusted about two to three times a month when I am riding regularly. I have so far had 3 new chains, the bottom bracket replaced and the cables and housing replaced 3 times in the last 2 years. It is really noisy and clunky going into gear and sometimes the chain refuses to move past the middle of the small ring, which is quite the workout on a long mountain climb. I live in the "Burbs" of Denver and Climb regularly. I have another, cheaper, bike, " a aluminum Trek with 105 components that work reliably and are very quiet compared to my Durace components on my Carbon Orbea. Question>>> could I need new shifters or is it a frame problem??? Bummed about my expensive, beautiful bike in Denver.