Open Source TBS6980/1 driver
As a result of being rather fed up with the poor performance of his TBS6981, particularly since upgrading to TVH 3.4, Luis Alves decided to take it upon himself to investigate.
He set about writing his own version of the drivers, based on analysis of the TBS drivers and using an existing OSS driver (with similar demod chip) as a reference. He has now completed this driver and the result of his analysis is that the TBS driver has some fundamental issues that make failures very likely.
His driver is now complete and relatively easy to install (you do still need to extract firmware from the official drivers, but instructions to do this are provided). In addition to this he's also hoping to write a driver for the 6984 which shares the same demod chip. He also hopes to get the driver submitted upstream so that it becomes a standard part of the Linux kernel. See his github wiki.
We would strongly recommend that all users of the 6980/1 switch to this driver ASAP.
For those that are interested, we have been trying to have a dialog with TBS's driver maintainer, unfortunately the results so far have not been great. You can read the current state of things on the Tvheadend blog