Alan Davies stars as Jack the dog, observing Sarah (Claire Goose), her clothes, her little ways, all with the ironic devotion of a really clever pet. Sarah has a boyfriend, Adrian (Darren Boyd), on whom Jack is not at all keen. She also has an annoying mother (Deborah Norton). We can hear Jack's inner thoughts. No one else can. By Graeme Garden, from an original idea by the late Debbie Barham.

We're circling Buddha of Suburbia territory with this new sitcom by Suk Pannu, about Bharat, a suburban guru (Vincent Ebrahim), his disciple Henry (Tim Key) and Mrs Sidhu (Shelley King), his termagant receptionist. Bharat's advice is much sought after but what he advises (times of weddings etc) may depend on what's on TV that afternoon. Yet despite his devotion to Quincy, he wants the younger generation to take him seriously.

Mitchell is currently chairing a Monday evening game show, The Unbelievable Truth, in which comedians who appear on every other Radio 4 game show compete to see how many facts they can disguise in a three-minute web of fiction. He undoubtedly gives a lift to the otherwise predictable proceedings.

Radio Review

When their sketch show, That Mitchell and Webb Sound, first appeared on Radio 4 a few years ago, they weren't yet celebrities and their show was fresh, funny, inventive, daring.

Who do you think you're laughing at?

Down the Line is a Radio 4 comedy show that pretends to be a live phone-in but is actually a brilliant group of comedians making fun of such programmes. Gary Bellamy sounds like someone you'd hear on a local, rather than a network, station. But here he is on serious Radio 4, asking, "War: what is it good for?" and "Chocolate: are we too serious about it?" and "Toothpaste: has it gone too far?".

Armando Iannucci's radio show is a bit of a teeth-clencher... let's examine the components.

It's a sort of chat show, with three guests, except they aren't allowed to chat. They are there to make jokes on topics, presumably of which they have had notice, chosen to reflect the week's events. On Friday these included national holidays (Get Carter Day, suggested Will Smith, to rare studio audience silence), unlikely headlines (E.coli has entered the Big Brother house, offered Iannucci), David Cameron choosing a Benny Hill song on Desert Island Discs (here Natalie Haynes began talking, bafflingly, about shoes), who in public life you would like to kill and why (Clive Anderson pointed out that killing people is wrong, but Will Smith insisted that he still wants to kill Alan Rothwell for stealing his Action Man, the one with a parachute).

Iannucci joined in competitively and did solo riffs on why he hates Apple (his iPod froze) and his local gym. Croquet figured largely, of course, so largely that on Saturday, after the repeat, the weatherman said it would be a wonderful afternoon for it if the subject hadn't already been malleted to death.

Could it be that none of Iannucci's guests had spent enough time thinking what to say? Is it possible that Iannucci himself, back in 1990, when he was putting together the genuinely revolutionary On the Hour (and sweeping aside the News Quiz team waiting to get into the studio after him), would have allowed this show on air? I doubt it.

I think he's bored with the news and with radio. He's exhausted. He's had an exceptionally busy and productive year. Another, during which he will also set up the BBC's new comedy workshop, lies ahead. He has given energy and intelligence to some truly major work. Armando Iannucci's Charm Offensive is, alas, the dregs.

Joke's over for the phony phone-in

Radio is not so short of comedy that it needs to accommodate vanity projects, and its audience will make up its own mind, without benefit of publicity stunts, whether Down the Line is good enough to stay.

Then, in the comedy buffer zone, came The Blagger's Guide, half an hour of comedian David Quantick, a sort of mock-lecture on various musical genres (last weekend: prog rock, from Pink Floyd to Kate Bush), with just too much solemn expertise showing through for the mockery quite to work. In other words, it was an anorak pretending to be a torn T-shirt.

Now here comes autumn, with Another Case of Milton Jones on Thursdays to prove again that Radio 4 can make you stony-faced quicker than botox. Milton Jones is described in the Radio Times as 'the Perrier Award-winning king of the one-liners'. Maybe the Perrier judges that year were all aged 11.

Jones's jokes are of the variety that might appeal to little Chesney on Coronation Street, the red-haired child whose japes include putting soot on the eye pieces of binoculars.

Most of Jones's revolve around word confusion ('under budget' turns into 'under Budgens' which, in a sketch about architecture, leads to a project ending up beneath a grocery shop), or word association - for example, 'Brazil' leads to 'nut' and 'nut' leads to 'madness'. If by this time you'll accept an eighth of a laugh, or even a sixteenth, Milton (and his adroit tape editor) eventually came up with the goods in a sketch about running a sweet shop for the stars, in which George Michael asked for a Wispa, Chuck Berry a Rolo, Whitney Houston for a Yorkie and Elvis Costello said it was a good year for the Roses.

Welcome return of the school series that has already defied the rules of radio comedy, still produced by the virtuoso of casting and subtle direction, John Fawcett Wilson. It's as good as ever.