Joan i had a very similer problem to yours with clearwire and probably from the same base station. Clearwires main basestation in the area is at the top of Jamestown rd near the FAS training centre and that single base station services the entirety of finglas, ballymun and St. Margarets (where i am) so the load on that mast is massive as you are seeing with your speed problems. I spent weeks and weeks ringing and e-mailing clearwire with rubbish speed results and finally got an engineer on the phone who told me that the problem all along is that the service in the area is massively oversold and the load on the mast is double what it should be, so the only solution is to add a load of sectors to the mast to help out. Unfortunatly asfar as he knew nothing was sceduled to be done to that mast for atleast 6 months to a year as company policy was to keep putting up masts in area's with no service and not improving the masts that are already inplace.
The story ends when i demanded to be released for the contract and refused to pay my final months payments because of their useless service and am now an eircom dsl broadband customer and a lot happier with the service.
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