Subtitles disappearing - possible work around NOT involving power cycle!

[Thondwe]

So we have Accessibility/subtitles switched on, and we have watched some stuff with subtitles- then it stops working, even though though they are available on the program - so found by accident that if this happens, hitting ? Once to get the subtitles selection bar, then ? again to get the SkyQ help, and then exit magically gets them back on!  

working theory if you turn skyq on when the default channel/program  has no subtitles then they break until this is done? 

anyone else confirm this pattern?