for the moment we accept a very small tick with mpg123

play-test.rkt

@@ -36,6 +36,7 @@
 
 (sl-log-to-display)
 (define wav-output-file #f)
+(define seeked #f)
 
 (define (audio-play type ao-type handle buf-info buffer buf-len)
   (let* ((sample (hash-ref buf-info 'sample))
@@ -46,6 +47,11 @@
          (channels (hash-ref buf-info 'channels))
          (bytes-per-sample-all-channels (* channels bytes-per-sample))
          (duration (hash-ref buf-info 'duration))
+         (cond-seek (λ ()
+                      (when (= (round current-seconds) 10)
+                        (when (and (= current-file-id 3) (not seeked))
+                          (set! seeked #t)
+                          (audio-seek current-audio-h 97.0)))))
          )
     ;(displayln buf-info)
     (when (eq? ao-h #f)
@@ -74,9 +80,7 @@
       (let* ((buf-size (ao-bufsize-async ao-h))
              (buf-seconds (exact->inexact (/ buf-size bytes-per-sample-all-channels rate))))
         (second-printer buf-seconds)
-        (when (= (round current-seconds) 10)
+        (cond-seek)
-          (when (= current-file-id 3)
-            (audio-seek current-audio-h 97.0)))
         (when (> buf-seconds 5)
           (letrec ((waiter (λ ()
                              (let ((buf-seconds-left (exact->inexact
@@ -98,9 +102,7 @@
                                        (ao-set-volume! ao-h 150))
                                      (when (= (round current-seconds) 40)
                                        (ao-set-volume! ao-h 100))
-                                     (when (= (round current-seconds) 10)
+                                     (cond-seek)
-                                       (when (= current-file-id 3)
-                                         (audio-seek current-audio-h 97.0)))
                                      (waiter)))))
                              ))
             (waiter))))