Viewers of the opening episode of Rillington Place were left frustrated after struggling to make out the dialogue in the BBC's latest drama.
The three-part serial dramatises the crimes of John Christie, one of Britain's most notorious serial killers who was active during the 1940s and early 1950s when he murdered at least eight women - including his wife - inside his flat at 10 Rillington Place in Notting Hill, London.
Actor Tim Roth - who plays Christie - was lauded for his performance although viewers complained of having to use subtitles because of "whispering" and "murmuring".
However, some users pointed out that Christie had been gassed during World War One and therefore had a low, whispering voice.
The comments come after BBC dramas Happy Valley, starring Sarah Lancashire, and Jamaica Inn were also plagued by sound problems.
The BBC's TV chief, Charlotte Moore, previously pledged to tackle problems with sound on the corporation's shows.
"It is incredibly hard to get to the bottom of where things go wrong. It's often several circumstances and it's quite hard to isolate if there is one particular problem," the director of BBC content has said.
"It is often several different problems coming together. Sound is a very exact science."
BBC1 drama Jamaica Inn sparked more than 2,000 complaints about inaudible dialogue.
BBC director-general Tony Hall recently vowed to look into the sound problems experienced by viewers of Happy Valley after the second series of the BBC One show sparked hundreds of complaints from viewers over the "shocking" sound quality.