PC環境変えたせいかどうかは知らんが、Win10 x64 2004でmedia-autobuild_suite使うと以下のエラー(一部修正あり)でビルドできないんだけど・・・
バグ？

Likely error (tail of the failed operation logfile):
| SRTO_SENDER
src/libavformat/libsrt.c: In function 'libsrt_setup':
src/libavformat/libsrt.c:409:5: warning: 'srt_socket' is deprecated [-Wdeprecated-declarations]
409 | fd = srt_socket(cur_ai->ai_family, cur_ai->ai_socktype, 0);
| ^~
In file included from src/libavformat/libsrt.c:24:
"srt.h":735:41: note: declared here
735 | SRT_ATR_DEPRECATED_PX SRT_API SRTSOCKET srt_socket(int, int, int) SRT_ATR_DEPRECATED;
| ^~~~~~~~~~
make: *** [/build/ffmpeg-git/ffbuild/common.mak:59: libavformat/libsrt.o] Error 1
make failed. Check "ab-suite.make.log"
This is required for other packages, so this script will exit.
16:07:02 Creating diagnostics file...

Attach "logs.zip" to the GitHub issue.
Make sure the suite is up-to-date before reporting an issue. It might've been fixed already.
Try running the build again at a later time.