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documentation/exploring_feature_notes/another_hdmi_bug.md

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+# hdmi drop out bug
 
+some time between when i did compatablitiy testing , and now - high res videos now often (and conistently cause hdmi drop outs. all 1080 do , and some 720 also) - on my hdmi-to-vga computer display. 
+
+also (possiblely related) when trying it on full hdmi projector, it drops out playing all video no matter the resolution ! whats going on ?
+
+some research sugests that not enough power can cause this problem.
+ possible fixes / things to rule out include : 
+ 
+ - trying signal-boost in config
+ - try overclocking the pi
+ - try an old version of the code
+ - try an old version of firmware
+ - try changing some other config settings (camera mode etc)
+ - try creating a new img from old img (with bare minimum) and update piece by piece until it doesnt work.
+ 
+## results:
+
+### vga-hdmi display
+
+- signal boosting didnt help ,
+- old version of code didnt help
+- old firmware improved a little bit but didnt fix
+- changing config etc didnt help
+- turning off raspi2fb didnt help
+
+### drastic measures ! :
+
+- flashed a new sd with old raspbian from last year. only installing the minimal to play video.
+
+- while running old code it plays better but not perfect - still drops from time to time but mostly working.
+- tried installing some newer dependacies , still running old code :
+
+# solved ?
+
+by chance i tried switching the video output to composite and back - somehow after this the hdmi plays 1080 videos just fine. no idea why or when it was introduced , but i created an action to run this on startup and seems fine now. phew.