Error Converting Audio mkv audio file from DTS 6.1 ch to .ac3

Hey guys!
I could use some help with a problem I’m having when converting audio formats.
I was working with eac3toGUI v2 to convert my .mkv audio file from DTS 6.1 ch to .ac3.
However, the conversion process keeps getting aborted, as seen in the picture below:

The AC3 encoder received a non-supported data format < float, 7, 64, >. Aborted at file position 262144.
Expecting your help
Thanks.
