Jack Trouble ...

BASS 666

ok will do ...

BASS 666

technika 40 f22b fhd ...
online manual ...   http://www.umc-uk.co.uk/Manuals/Technika/40 models/User Guide TEC-MAN-0086 32F22B-FHD-DVD-32F22WFHD-DVD-40F22B-FHD-DVD-UKROI versWEB.pdf

JayCee

EDIT.
Try going into the sound menu (Page 20 of user manual) and toggling the “Digital Output” to “On” or “Off”
I once came across a TV design that weirdly gave you the option of headphone or digital output (it was one or the other) and there was no headphone output if the digital coax or optical out was in use.

After reading the manual I agree there are no options in the sound settings menu which would cause that behaviour.
I suspect rather than just use the mechanical switching action of a standard 3.5mm jack socket It may be a software design to ensure the TV always defaults to the internal speakers at switch on.
You could try spraying some switch cleaner into the socket and plugging/unplugging the headphones a few times in case it's just an intermittently duff socket.

BASS 666

thanks Jay .. iv done what you said and more a few times with the same result every time ... if it is the software making it go to tv speakers when turned back on then i don't know what they were thinking ... now i have to get a new tv because these people thought it was a good idea to change something that has been around for decades ... absolute joke of a company ....