Kept getting failed or corrupted game demo downloaded from Live

I have been trying to download game demos from Xbox Live over the last few days. Sometimes it would successfully downloaded the demo but frequently, the demos downloaded part way, got stuck as it started or completed download but in the hard drive Memory, Demo, it showed the downloaded game is still a cache.

Once it corrupted the hard drive with error E68 (right bottom red light). I managed to solve that by deleting the last 1.2GB demo game that it downloaded.

Sometimes the hard drive space would disappear with no incomplete game cache.

Once when I started Table Tennis, it tried to download the update but got stuck. After I pressed "A" button starting the game to clear the update, it refused to run the game anymore with error, the disc is dirty. I had to Y+X,X,LB,RB,XX to clear the hard drive cache before the game would start again.

It seems if Xbox Live game demo or update download fails, it would randomly corrupted the hard drive. All I know is I have my 360 for 11 months not connected to Live and never once it got any corruption or error. In a few days it connected to Live downloading demos, it corrupted the hard drive several times already.

Anyone having this kind of behavior with Xbox Live downloading demos over the last few days?

It does seem to occur mostly on demos that are over 1GB in size. I did manage to download C&C for other demos like Dead Rising can never download properly.