Well, Birchy, on first reading I thought you'd written 'sikh' rather than 'sikth', but you're right, some people - media types or not - do pronounce it that way. Perhaps they always have. And, as for standards of pronunciation slipping, well, that depends on your viewpoint. If you subscribe to a strictly RP ethos of pronunciation, then the prevalence of regional - especially Esturine - accents on TV and radio would be irksome. However, if you have a more demotic and egalitarian stance, then it might be perceived as a good thing.