diff --git a/gnu/services/audio.scm b/gnu/services/audio.scm
index 345d8225b2..37f2efa479 100644
--- a/gnu/services/audio.scm
+++ b/gnu/services/audio.scm
@@ -24,6 +24,7 @@ (define-module (gnu services audio)
   #:use-module (gnu packages mpd)
   #:use-module (guix records)
   #:use-module (ice-9 match)
+  #:use-module (ice-9 format)
   #:export (mpd-output
             mpd-output?
             mpd-configuration