There are a few changes you can make to your Tablo's setup to eliminate or reduce buffering.
Head over to the Tablo web app at http://my.tablotv.com/ and navigate to the Settings menu.
Under the 'Recording quality' section switch to 'HD 720p - 3Mbps'. This new setting will become active for all future recordings and Live TV - it will not become active for any old recordings.
Next, scroll to the bottom of the Settings page and turn OFF the 'Enable fast live TV startup' toggle.
If you continue to have buffering problems, try hardwiring your Tablo directly to your router with an Ethernet cable. The Tablo's video is sent directly over your router's network. Poor Wi-Fi connectivity will result in buffering, while an Ethernet connection is generally significantly faster and more stable.