5d3 in coma when in video mode

[RobPan]

The 53D in video mode sometimes acts strangely. I presumably had pressed the wrong button when the screen image suddenly froze and could not be resuscitated back to life. There was nothing I could do, the camera was in a deep coma so to say. Even shutting off the camera (with the on-off switch) did not help, all I could to was removing the battery.
After the battery was replaced the camera was back to normal again.
Irritatingly, I could not reproduce the problem, though I tried several times. Therefore I do not know which series of key presses induce a coma-like state like this.
Does anyone recognize this problem?  Any solutions  (where is the WRONG button?)? This has happened twice now; I have had the camera for three month, taken just over 1400 pictures and shot 19 videos.

Thanks for your replies!

Kind regards,

RobPan.

[Mt Spokane Photography]

Are you using a CF Card or a SD card?  SD cards write very slowly and might cause a freezeup.  CF cards tend to write much faster.  That probably is not your issue, but its at least one thing to eliminate.  BTW, even a SDHC card rated at 95 MB/sec can write at less than 10MB/sec, so don't get fooled by specs that quote read speeds, or write speeds for blank cards, which only happen with a new card, or with one that was erased (low level format).

[RobPan]

I have a Sandisk Ultra CF card, 16 MB, 30MB/s. That is a lot faster than I can write myself, but perhaps very slow for a modern CF card (I far know too little about memory cards).
Can slow CF cards cause problems?

Kind regards,

RobPan