Update README.md (#66)

Author: GioF71

README.md

@@ -69,7 +69,7 @@ DEVICE_NAME||Device name.
 DEVICE_TYPE|speaker|Displayed device type: `computer`, `tablet`, `smartphone`, `speaker`, `tv`, `avr` (Audio/Video Receiver), `stb` (Set-Top Box), `audiodongle`, `gameconsole`, `castaudio`, `castvideo`, `automobile`, `smartwatch`, `chromebook`, `carthing`, `homething`. Defaults to `speaker`.
 DEVICE||Audio device to use. Use `?` to list options if using `alsa`, `portaudio` or `rodio`. Enter the path to the output when using `pipe`. Defaults to the backend's default.
 FORMAT|S16|Output format: `F64`, `F32`, `S32`, `S24`, `S24_3`, `S16`. Defaults to `S16`.
-ENABLE_CACHE||Y or y to enable, uses correspondent volume.
+ENABLE_CACHE||`Y` or `y` to enable, uses correspondent volume.
 ENABLE_SYSTEM_CACHE||`Y` or `y` to enable, uses correspondent volume.
 CACHE_SIZE_LIMIT||Limits the size of the cache for audio files. It's possible to use suffixes like `K`, `M` or `G`.
 DISABLE_AUDIO_CACHE||`Y` or `y` to disable.