Steps to reproduce:

1) Download attached project 'reproProject.zip' and open in Unity
2) Open 'demoVideo' scene and press Play
3) Click on 'Play' button
4) After ~2 seconds, click on 'Stop' button
5) Click on 'Play' button again
You will see that video won't play

Expected result: Video should start playback after stopping it and pressing on 'Play' button again
Actual result: Video never plays

Reproduced with:
5.6.0f1, 5.6.1p3, 2017.1.0b9, 2017.2.0a3

Also reproduced on android device:
Samsung SM G925F (Galaxy S6 Edge)*, OS:7.0, CPU:arm64-v8a, GPU:Mali-T760, Build:samsung/zeroltexx/zerolte:6.0.1/MMB29K/G925FXXU5DQA7:user/release-keys