It looks like your admins may have set the following IT Policy setting:

Password policy group > Periodic Challenge Time IT policy rule

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This rule specifies the security timeout interval (in hours) after which the BlackBerry® device locks and prompts the user to type a password, regardless of whether the BlackBerry device has been active during that interval.

Default setting: If you set the Enable Long-Term Timeout IT policy rule to True, the security timeout interval is turned on and set to 1 hour by default.

Usage: Type a periodic challenge time to shorten or extend the security timeout interval to a value within the range of 1 hour to 24 hours.

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If indeed they have set this ask them to remove it if they can. Did you notice how long it would take for this auto-lock to kick in?

If it takes less than an hour to kick in, then unfortunately you need to perform some form of key click or movement to work around the inactivity timeout as the video playing does not appear to meet the requirement for activity on the device. Either way, no way around it.

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