You may have your bandwidth speeds set to allow ElephantDrive little bandwidth. To see how you can change the bandwidth speed, please see the Bandwidth tutorial.
We are constantly working to increase the speed of our transfers. In most cases, the limiting factor is the connection speed at the source. This can be a challenge during the initial upload process, but our differentiation tools will dramatically speed up subsequent backups.
Another limiting factor in the speed of transfer is our encryption process. The cryptographic alogrithms are computationally intensive and can slow down the process a bit, especially with larger files. This is the trade off for increased security and privacy. We will however begin enabling un-encrypted transfers for users who specifically request it which can increase the overall rate of transfer. If you are interested in this, please let us know.