Reliance WiMax

I am also facing the same problem with Reliance WiMax. The connection is quite erratic, at times it works quite smoothly but at times it just dosent get a IP for hours together. I tried calling up the helpdesk but as all most of us here have experienced they are crap. Also the sales guys dont really understand what and where is the problem. Have any of you manged to resolve this problem when one just cant get an IP. if so please let me know the solution