Digital Products – Video Download not complete

Hi,
I am selling digital products on my WordPress website: http://www.compostelle.ca
I’ve uploaded the videos through my server (some of them are 1.42G) and am selling them through woocommerce.
The payment and email confirmation is working fine but the download seems to stop after a few minutes.
Do you know what could be the problem?
After the purchase, when the link to the video is sent my email and downloaded, the browser indicated that it will be about 1h to upload but after a few minutes the video download ends and only the first 5-10min are available to watch.
Any help would be greatly appreciated!
Claude