No picture on Live TV after reenter

[cdr_pro]

after startup of my htpc and first start of npvr, live tv works fine.
when i leave the live tv and reenter it, i get only a black screen.

nearly the same problem occures when i have scheduled two recordings.
after startup of my htpc and first start of npvr, the first recording works fine.
the second one has corrupted picture and sound.(see attchement)

has anyone an idea?

i have attched my logs.

[Reddwarf]

In settings -> Misc screen, try unticking the "Keep digital graphs constructed". It worked for me on a very similar issue.

[cdr_pro]

Thanks for your hint, but it's allrady unticked. :-(

[cdr_pro]

With GraphStudio I have figured out, that if I exit the live tv the graph stays constructed.
If I enter and exit the live tv four times, GraphStudio shows up four graphs. When I exit npvr all four graphs disappear.

An other thing, that I have found out is, that if I select the Overlay Renderer npvr always uses the EVR.