There are 2 versions of Thetis available. There is a version for Apache-Labs Anan radios, and another that supports the Hermes Lite 2 and Hermes Lite 2 Plus radios. Anan's and Hermes' are similar but NOT the same. Be sure to use the correct version to avoid issues.
1. In the past, Thetis has been the prime SDR software used on Apache-Labs Anan radios. It has been the child of many, but Ritchie (Ramdor) MW0LGE has parented Thetis for over 2 years now. Since he became involved, many bugs were fixed and features added that have made it a solid piece of SDR software. It targets Apache-Labs Anan radio's and their different models. Notice that I did not say Hermes Lite 2 radios! While Ritchie's Thetis versions will work with an HL2, some issues will likely surface.
2. With the increasing popularity of the Hermes Lite 2 transceiver, something more was needed because of the differences in the hardware. While it could be made to work, Ritchie's Thetis did not directly support many of the hardware differences. Reid Campbell, MI0BOT took Ritchie's Thetis program and modified it to support the HL2. Install Ritchie's Thetis first and then Reid's version using his installation instructions. The two pieces of software will install in different directories. Both are required for Reid's Thetis for HL2 version to work correctly.
To find out what version of Thetis you are using, check the main screen in the upper left hand corner. For Ritchie's version it will say "Thetis vx.x.x.x" (followed by some other stuff). For Reid's version, it will say "vx.x.x.x" (followed by some other stuff) and then "HL2".