Vodacom reception is not what they claim

Can anybody at Vodacom explain to me why watching sport in Maclear through a Vodacom connection is impossible as it just keeps on buffering on the lowest Supersport resolution, while the icon on the device shows it is 3g hsdpa which should be able to easily stream even hd resolution. It is the same across devices, and there is no problem with signal strength. This problem also occurs in the early evening when one tries t watch tv through a Vodacom connection