Fully document the "no audio → too fast" problem.

docs/faq.md

@@ -101,6 +101,9 @@ If games are running way too fast, here's some things to check:
       - If you want the game to be silent,
         tick "Mute Audio" in
         [the Settings menu](interface/higan.md#the-settings-menu)
+  - If you can't connect speakers or headphones to your computer,
+    you did but it didn't help,
+    try enabling the secret [video synchronization][vsync] option.
 
 [vsync]: #i-see-tearing-when-a-game-scrolls-how-can-i-enable-vsync
 

docs/guides/drivers.md

@@ -121,12 +121,11 @@ On Linux:
     PulseAudio's OSS emulation,
     or not work at all.
 
-TODO: If the audio driver is set to None,
+**Note:**
-or you have no audio device,
+By default,
-Sync Audio does not work
+higan uses the audio driver to regulate its emulation speed.
-and games will run in fast-forward
+If games run too faston your computer,
-unless you enable Sync Video.
+see [Games run too fast](../faq.md#games-run-too-fast) in the FAQ.
-https://board.byuu.org/viewtopic.php?p=44138#p44138
 
 Input
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