A council has defended its plan to spend about £50,000 replacing audio equipment at a building which opened almost five years ago.

On Friday councillors will vote on whether to ask for quotes for the new equipment in the council chamber at West Suffolk House in Bury St Edmunds.

Members of the public often have difficulty hearing what is being said during meetings and sometimes councillors have to shout because the microphones do not work properly.

West Suffolk House is jointly owned by St Edmundsbury Borough Council and Suffolk County Council.

A borough council spokeswoman said: “We are looking at replacing a heavily-used audio system for the council chamber at West Suffolk House which was installed when the building opened five years ago.

“Some of the equipment needs replacing through normal wear and tear. However, since the building opened, demand has also outstripped the capacity of the audio system, so that when mobile phones, laptops and other equipment are used in the building and surrounding offices it affects quality and reliability.”

She said a replacement system was likely to cost about £50,000 and the funding would come from the building’s maintenance and equipment budget.

Independent councillor Trevor Beckwith said it seemed a lot of money to pay out when the building was only five years old. “To me it seems rather soon after a brand new building with all the new gear in it and planning that went ahead to get up and running,” he added.

David Nettleton, who is also an independent councillor, said once when he chaired a meeting he found he was having to shout so the public could hear. “They have come to hear what’s being said so it’s not very satisfactory,” he added.

He said there had been numerous issues with the new council offices, including the level of noise because of the open-plan design. He said: “That building has been there since March 2009 – we’re talking about five years – and we still don’t have everything sorted out at that building.”

Councillors will vote on the plans for the new audio equipment at a meeting of the Shared Offices Joint Committee.