Time capsule goes for "sleep mode" ?

Hey Guys,

Im using a Time Capsule (called TC below) 2 TB, the latest version, mostly for two things;

I download files to directly to the TC harddrive and i also store some of my music on it.

The first problem is that when i download files directly to it... The download speed goes up to a couple of Mbit/s and then down to zero again... Then up again, and down to zero again. It's unstable. This dosen't happen when i download the files directly to my Macintosh HD.

The second problem is when i want to play music from the TC, for example on Itunes or on Traktor... It has a long delay for a couple of seconds from the time that i press play and the actual time that the song starts playing.

Does anyone have the same problems?

I think it is because the TC goes in some kind of "sleep mode" and therefore it has to "wake up" to be able to play the files on it, or store files on it.

Does anyone know if it is possible to turn off the sleep mode?

Thanks in advance!