To misquote Marx (Karl, not Groucho), comedy repeats itself, the first time as farce, the second time as a tragedy. The early days of broadcasting bred comedians whose work lives on in the nation’s marrow. But being Frankie Howerd or Kenneth Williams or the Steptoe actors was no laughing matter.

Jabberwocky is all the more enjoyable once you get past what it isn’t; Terry Gilliam’s 1977 directorial debut is a medieval romp starring Michael Palin and a short-lived Terry Jones, but audiences shouldn’t expect a Monty Python film.

Even seemingly immortal singers grow old. Sir Bryn is closer to the "Martinmas summer" of Shakespeare's and Verdi's Sir John than when first he put on the fat suit at the Royal Opera 18 years ago. Even if he walks the gouty walk that matches the belly, vocally he seems richer than ever.

It seems to be the season for light entertainers to show us their musical chops, with Nick Knowles, Bardley Walsh and Jason Manford all doing their level best to prove that they are All Round Entertainters. Matt Berry, however, provides a rather different twist on the comedian-troubadour trope.

Although primarily known for "Guns Don’t Kill People, Rappers Do", Goldie Lookin' Chain have actually been around longer than you'd imagine. The Welsh comedy collective was formed at the turn of the millennium, and Fear of a Welsh Planet is, staggeringly, their 20th LP. Back in the day, the boys would wear shell suits and rap about council estates. But that was years ago. Surely, by now, they've moved on?

Not a bit of it. On the new album, the lads still sound like a Welsh version of Insane Clown Posse with added blue humour. The rudest track is "Sex People" which discusses "shooting each other in the ass with a sex gun". The rest aren't far behind: The narrator of "Bonk Eye" declares "your missus thinks I'm staring at her tits all night", while "I Got A Van" contains the immortal lines, "We don't need to go to a hotel/We've got my van if you don't mind the smell".

Still, no-one expects Oscar Wilde from GLC. Surely, the main thing is simply whether it makes you laugh. Unfortunately, there's precious little here to raise a decent smile. Even those few lines that do possess a certain goofy charm are ruined by GLC's awful DIY approach to music-making. Much of the album sounds like it was played on a Casio keyboard with tinny beats that wear you down like Chinese water torture.

You wonder why the boys don't try something new. Especially given the goodwill the band tends to generate. Their former singer, Maggot, was once a cultural icon (of sorts). And let us not forget that GLC were the inspiration behind the hilarious YouTube hit "Newport State of Mind". But GLC have long since stopped being funny. On their website, the band joke about not wanting to be seen as Oldie Looking Chain. It's not their age that's the problem. It's doing untold versions of the same bad joke.

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Overleaf: Goldie Lookin' Chain's video for "I Got a Van"