Same symptoms here. Two different iPhone 4 (one Telia provider, one Telenor provider) with the latest iOS and latest Air Video app streaming from two different Air Video servers, one hosted on Mac OS X the other on Debian Linux. Both work over WiFi and both fail over 3G. I can confirm that rebooting the iPhone solves the issue. I'm suspecting a bug in the latest version of the Air Video app for iPhone.
pascalw wrote:I got the server piece up and running on a Debian Lenny server but it crashes on the server when I browse the media files using my iPhone. Looks like it occurs when it tries to create thumbnails: