I had Sky Broadband installed 8 days ago and have been checking the speeds daily on the thinkbroadband speedtester. The first few days both download tests were more or less the same getting up to around 15mb. However in the last two days the ttb download number has dropped to be around half the other. The ttb is showing at 7 or 8 whilst the other is around 17. Is there any reason why this may be or is it a sign something is wrong?