Are you using Beta (latest untried version 4.11.1 or 4.10.9 the latest stable version? Getting pro is not likely to help. You should find out what the problem is. Pro should only be installed if basic is working properly.
Many posts have been made recently about files awaiting sources as there are many files out there which will not download for a number of reasons.
Let us know what type of connection you have, who is your isp, and try to download any magnetmix file from
http://www.magnetmix.com/ and let us know what happens