Index: wp-includes/deprecated.php
===================================================================
--- wp-includes/deprecated.php	(revision 37616)
+++ wp-includes/deprecated.php	(working copy)
@@ -3329,7 +3329,7 @@
 function wp_convert_bytes_to_hr( $bytes ) {
 	_deprecated_function( __FUNCTION__, '3.6', 'size_format()' );
 
-	$units = array( 0 => 'B', 1 => 'kB', 2 => 'MB', 3 => 'GB', 4 => 'TB' );
+	$units = array( 0 => 'B', 1 => 'KB', 2 => 'MB', 3 => 'GB', 4 => 'TB' );
 	$log   = log( $bytes, KB_IN_BYTES );
 	$power = (int) $log;
 	$size  = pow( KB_IN_BYTES, $log - $power );
Index: wp-includes/functions.php
===================================================================
--- wp-includes/functions.php	(revision 37616)
+++ wp-includes/functions.php	(working copy)
@@ -237,7 +237,7 @@
 /**
  * Convert number of bytes largest unit bytes will fit into.
  *
- * It is easier to read 1 kB than 1024 bytes and 1 MB than 1048576 bytes. Converts
+ * It is easier to read 1 KB than 1024 bytes and 1 MB than 1048576 bytes. Converts
  * number of bytes to human readable number by taking the number of that unit
  * that the bytes will go into it. Supports TB value.
  *
@@ -259,7 +259,7 @@
 		'TB' => TB_IN_BYTES,
 		'GB' => GB_IN_BYTES,
 		'MB' => MB_IN_BYTES,
-		'kB' => KB_IN_BYTES,
+		'KB' => KB_IN_BYTES,
 		'B'  => 1,
 	);
 
Index: wp-includes/ID3/getid3.php
===================================================================
--- wp-includes/ID3/getid3.php	(revision 37616)
+++ wp-includes/ID3/getid3.php	(working copy)
@@ -1299,7 +1299,7 @@
 			// end of the comments and the end of the file (minus any trailing tags),
 			// because the page sequence numbers of the pages that the audio data is on
 			// do not match. Under normal circumstances, where comments are smaller than
-			// the nominal 4-8kB page size, then this is not a problem, but if there are
+			// the nominal 4-8KB page size, then this is not a problem, but if there are
 			// very large comments, the only way around it is to strip off the comment
 			// tags with vorbiscomment and MD5 that file.
 			// This procedure must be applied to ALL Ogg files, not just the ones with
Index: wp-includes/ID3/module.audio-video.riff.php
===================================================================
--- wp-includes/ID3/module.audio-video.riff.php	(revision 37616)
+++ wp-includes/ID3/module.audio-video.riff.php	(working copy)
@@ -1693,7 +1693,7 @@
 									}
 									$RIFFchunk[$LISTchunkParent][$chunkname][$thisindex]['data'] = $this->fread($chunksize);
 								} elseif ($chunksize < 2048) {
-									// only read data in if smaller than 2kB
+									// only read data in if smaller than 2KB
 									$RIFFchunk[$chunkname][$thisindex]['data'] = $this->fread($chunksize);
 								} else {
 									$this->fseek($chunksize, SEEK_CUR);
Index: wp-includes/ID3/module.audio.mp3.php
===================================================================
--- wp-includes/ID3/module.audio.mp3.php	(revision 37616)
+++ wp-includes/ID3/module.audio.mp3.php	(working copy)
@@ -1372,7 +1372,7 @@
 
 				if ($SynchSeekOffset > $sync_seek_buffer_size) {
 					// if a synch's not found within the first 128k bytes, then give up
-					$info['error'][] = 'Could not find valid MPEG audio synch within the first '.round($sync_seek_buffer_size / 1024).'kB';
+					$info['error'][] = 'Could not find valid MPEG audio synch within the first '.round($sync_seek_buffer_size / 1024).'KB';
 					if (isset($info['audio']['bitrate'])) {
 						unset($info['audio']['bitrate']);
 					}