Some Apps work better for this than others and some players do a better job at this.
- Make sure your either hardwired to your network or on 5Ghz Wireless.
- Clear the cache on the app
- reboot your home network including modem
- Test your network speeds
- Check your provider
- Try a VPN connection
- Lastly, Try a phone that isn't on your wireless. If that works then you know the issue is something with your network. 8 times out of 10 the issue will be something with your provider or configuration.
Tivimate and XCIPTV apps also handle buffering better than the smarters app.