I don't think so, use "opus-tools-0.2-opus-1.3" (https://www.opus-codec.org/downloads/) command line "opusdec --force-wav input.opus-| opusenc --bitrate 64-output.opus" is OK. The foobar2000 converter is OK too. They all use the same opusenc.exe.
Use audio conversion to convert a 7-hour opus file (128kbs) to an opus file (48kbs), and then it becomes 2 files, 1 file is 6 hours and 12 minutes, 1 file is 1 hour (part2), this is not what I need . Can you fix it?