TalkTalk has once again attracted the most complaints of any internet service provider (ISP), the fifth quarter in a row it has done so, with six complainants in every 10,000 of its customers, according to Ofcom.
The telecoms watchdog said the complaints mainly stemmed from "line faults and other service issues".
TalkTalk acknowledged the issue in a statement but said it believed it was making the right moves to address the concerns of its customers.
"While there will always be variations in the quarterly data, we are confident that the long-term trend is positive - fewer complaints, more calls being resolved first time and improving customer service," it said.
"There is more work to do, but we are confident that the measures we've put in place are paying dividends."
Faring better in the report were Sky and Virgin, who were the least complained about fixed broadband providers, with 1.7 and 1.8 complaints per 10,000 customers respectively.
In the mobile world complaints were much lower in terms of volumes.
Here, Orange was the worst offender, seeing a spike in complaints of 1.7 per 10,000 customers in the quarter, up from 0.7 in the previous period.
Ofcom attributed this to the firm's plans to increase the monthly charges for customers on existing contracts.
Orange said it was disappointed with the findings and said it would be working to try and improve in the coming months.
"We will take on board the findings from the Ofcom report, and continue to look to make improvements in the area of customer satisfaction through our existing employee training programme, customer feedback reviews and our investment in technology," it said.
Three customers were the second to be disappointed with their provider, with 1.5 complaints per 10,000 customers, due to disputed charges and poor customer service.
O2 maintained its position as the operator with the most contented users, with just 0.2 complaints per 10,000 customers.
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