Flickr - Uploading Problems

[jdag]

Any ideas as to why I often have trouble uploading to Flickr (I know, very general question).

I often have to cancel an upload and just try a few photos at a time as opposed to larger batches. I've tried large and small files. There doesn't appear to be a rhyme or reason.

I've tried both the web interface and the Flickr Uploadr application.

Thanks in advance, John