Some time ago I repaired an old 16" Philips CRT TV (CTX chassis, 16CT22.....something).
It has battery backup for settings and no default settings memory (e.g. green button).
When switched on, volume is extremely high and there is no way to set a lower default volume (every time you have to decrease volume manually).
I remember a tip :idea: found on internet (russian site maybe) about press and hold some button at power on or so to set a lower volume, but I can't retrieve now .