I have been having this problem for quite a while.
I shoot HDV and capture HDV to ProRes 422. My timeline settings are setup for ProRes 422 and 8 bit (best). 1480x1080.
Often times, I will have just ONE little clip that needs rendered...... it'll go through the process just fine and when it finishes, that one little clip will be rendered but then a ton of other clips on the timeline become UN-RENDERED and it becomes this vicious cycle of getting the entire timeline fully rendered. I don't get it! And it's not just one particular project. It happens on pretty much every new one. I've tried in and out points. That doesn't help. I have everything checked marked under the render all/render selection tab as well.
Any ideas on this? It's becoming a royal pain. Thanks so much!