A bizarre humming noise is being reported in parts of Montgomeryshire.

Peter Danks, of Llwyn Y Gog, Staylittle, has claimed the intermittent hum is driving him round the bend, and he's no idea where it's coming from.

"It sounds like the idling of a diesel engine, and it comes and goes with seemingly no pattern," said Mr Danks, who has lived in the area for more than 10 years.

"It began around three months ago," he said: "I woke up in the middle of the night and felt sick, so I went to the doctors and they said there is nothing wrong with my ears. It can start any time, and then stops randomly before starting again.

"The bedroom and whole front of the house seem to be the worst for it, and it does get quieter outside but then if I go out somewhere it can start again.

"It's getting me down now, I don't know what it is and I need to find out soon."

The strange phenomenon draws comparisons to the famous 'Bristol Hum' of the 70s, when hundreds of residents all claimed to be plagued by a low-level humming noise.

Philip Robinson, 50, a consultant ear, nose and throat surgeon at Southmead Hospital, Bristol, specialises in hearing problems.

He has seen a handful of patients who have complained of the hum over the past 15 years.

He said: "People have a mechanism for controlling loudness. If you are asleep at night and a lorry goes past, your brain does not wake you up, but if you hear a tiny creak on the stairs you will wake up. People who hear noise constantly find it is worse inside houses and worse if they fit double glazing.

"There are definitely some cases where there is an environmental source but more often it's inside the human being. I believe that psychology and relaxation is the way forward in these cases."