I'm unfortunately opening an old thread
@Arhu. Why don't you use AAC instead of Opus? Opus takes much more decoding time.
I did a test in foobar2000 v1.4 (with component "Decoding speed test"), testing the song "Ennio Morricone Conducts Morricone His Greatest Hits - The Good, the Bad and the Ugly: The Ecstasy of Gold".
"High priority: yes
Buffer entire file into memory: yes
Warm-up: yes"
Apple AAC@144kbps (using latest version with qaac_2.67, default setting),
"Decoding time: 0:00.174"
Opus@144kbps (using opus-tools-0.1.10-win64, default setting),
"Decoding time: 0:00.990"