Slingshot fibre slow

Hi All

Can anyone suggest why my download and upload speeds are so slow on slingshot fibre. We are staying at a friends place for a few weeks in Christchurch near Northlands mall and sometimes the connection is painfully slow. At other times it is acceptable. This one is 8:30 on a Wednesday evening. I had one that only made it to 0.79Mbps. Quite often my cellular connection is many times faster. Its not a good advertisement for slingshot for when we move into our new house.

Cheers

Steve