Thanks Marc,
HTC EVO 3D, US, Sprint, not rooted. New -- although actually it was a replacement unit sent by the company Sprint uses for insurance replacements, I don't remember their name. So it could possibly have been refurbished or something.
I believe the issue started quite soon after installing each app, though not immediately. Maybe within a week. But it's been a while since I started using pocket casts.
The issue has occurred both on wifi and 3G (and 4G) connections.
I don't stream anything else often enough to recall problems. Youtube generally works but I use it very seldom.
Thanks!