i have a sunpak pz40x as said and it playing up.
It wont turn on i have installed new batteries three times. i dont think it is the contacts as i have cleaned the battery contacts with a sandpaper and also a minimal abrasion file.
is there any place that will look at it
thought id pop a line to sunpak and see what they say
the flash has never been used outside and only minimal use because i only just started using it as ive never had the need for it ...