I recorded the show in HD and watched it later through the hi-fi with headphones. I have about 40% hearing loss (common for my age, I'm over 60) and often have difficulty with some TV dramas, but Strictly came across loud and clear .. no peaks or troughs as others seem to have experienced.
Modern flat screen smart TVs don't always have the best sound reproduction. The answer of course is a sound bar, but not everyone wants to have that extra clobber in their TV/Hi-Fi corner!