Launchpad currently recommends translating rhythmbox in Ubuntu Cosmic.

Template "rhythmbox" in Ubuntu Cosmic package "rhythmbox"

Language Status Untranslated Need review Changed Last Edited By
Cherokee 100.00  100.0% untranslated 1001 1001 0 0
Dakota 100.00  100.0% untranslated 1001 1001 0 0
Hawaiian 100.00  100.0% untranslated 1001 1001 0 0
Inuktitut 100.00  100.0% untranslated 1001 1001 0 0
Lakota 100.00  100.0% untranslated 1001 1001 0 0
Ojibwe 100.00  100.0% untranslated 1001 1001 0 0
Spanish 000.00  100.0% translated 0 1 1 13 13 2018-10-10 18:52:18 UTC 2018-10-10 Daniel Mustieles
Tlingit 100.00  100.0% untranslated 1001 1001 0 0
Yiddish 100.00  100.0% untranslated 1001 1001 0 0
[ Change your preferred languages... View template & all languages... ]
Key to this table: “Unchanged” means Translated
and “untranslated” means just that, Untranslated

Other versions of rhythmbox in Ubuntu