It’s not necessary to get pay software.
Eac3to will decode DD TrueHD using LibAV which is included and free.
For DTS HD MA conversion, it was a real surprise this year when the free decoder “dcadec” appeared. It’s now included with Eac3to as well (and I believe it’s also included in MPC-HC among other proggies). It’s still “being tested” because it’s so new, but I haven’t seen any complaints yet.
With Eac3to you can decode to most other audio formats including multichannel WAV, individual WAV files, change sample rate and bit depth, speedup/slowdown for framerate changes, etc.
For pretty much all your BD audio decoding and conversion needs, Eac3to is the gold standard any more.