Customers may be experiencing intermittent services and slower data speeds than usual due to this, iTWire has learnt.
A resident of the area said on Monday that there had been issues periodically for about five days.
A number of traders in the Stawell area had been affected by this, the resident said.
"We know how frustrating service issues are for our customers and we want to apologise for this.
"We also want to assure the community we’re working to get the issue resolved as quickly as possible."