Weekend Ft 14406

[HenHen]

7d - hairstyle for day with changes among strings (6,3) - F?I???W??
19ac- old bird drinking a drink to setter's union within the law (8) - M??????? (penultimate letter is M , if musical is correct in 20d below)
16d- abandon formality of funereal dress, with zeal swapping parts? - ???R?E?E
20d - what the cat said to the reaper recorded in show (7) - ??S?C?L - musical, but if so, why?

Help appreciated, with rationale.

Thanks

HH

[cancross]

20 d - recorded = sounds like, so mew + sickle

[Lie-in King]

7d Fright wig - 'Fri(day)' + anag 'with' (in) 'G (string x2)'
19a Monogamy (union within the law) - 'moa' (old bird, containing; drinking) 'nog' (drink) + 'my' (setter's)
16d Unfreeze (abandon formality) - anag 'funere(al)' + 'ze(al)' (swapped parts)
20d Musical - "Mew" + "sickle" (recorded; heard)

[HenHen]

thanks CC - got it !!

[HenHen]

And thanks to you too, Lie in King.