fix pip autodetect for grab

Origin commit data
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Branch: ni/coolstream
Commit: e068e948db
Author: TangoCash <eric@loxat.de>
Date: 2022-11-22 (Tue, 22 Nov 2022)


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No further description and justification available within origin commit message!

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This commit was generated by Migit

src/zapit/src/zapit.cpp

@@ -707,6 +707,7 @@ bool CZapit::StopPip(int pip)
 		pipVideoDemux[pip]->Stop();
 		pipVideoDecoder[pip]->Stop();
 #if !HAVE_CST_HARDWARE
+		pipVideoDecoder[pip]->setBlank(pip);
 		pipAudioDemux[pip]->Stop();
 		pipAudioDecoder[pip]->Stop();
 #endif