Citizens Advice has called for more to be done to ensure the voice of telecoms customers is heard.
According to a recent report by Ofcom, the proportion of broadband customers with a reason to complain went up from 13 per cent in 2016 to 15 per cent in 2017, largely because of slow and patchy connections.
Figures also showed that broadband customers are increasingly displeased with how grievances are dealt with, as satisfaction over the handling of complaints fell from 56 per cent to 50 per cent.
Citizens Advice pointed out that since broadband is now an "essential" service for many people, consumers deserve a service that "meets the demands of modern life".
"These new figures show that not all providers are delivering," said Gillian Guy, Chief Executive of the organisation.
She went on to point out that recent Citizens Advice research has found that loyal customers face higher prices in the telecoms market.
Ms Guy therefore repeated her call for the government to establish an independent telecoms consumer advocate.
This, she stated, would help address poor service and ensure people's voices are heard "in this increasingly important market".