diff --git a/Lib/aifc.py b/Lib/aifc.py
index e06b7766ef4..69d38dd2423 100644
--- a/Lib/aifc.py
+++ b/Lib/aifc.py
@@ -55,9 +55,7 @@
 #
 # Reading AIFF files:
 #	f = aifc.open(file, 'r')
-# or
-#	f = aifc.openfp(filep, 'r')
-# where file is the name of a file and filep is an open file pointer.
+# where file is either the name of a file or an open file pointer.
 # The open file pointer must have methods read(), seek(), and close().
 # In some types of audio files, if the setpos() method is not used,
 # the seek() method is not necessary.
@@ -90,9 +88,7 @@
 #
 # Writing AIFF files:
 #	f = aifc.open(file, 'w')
-# or
-#	f = aifc.openfp(filep, 'w')
-# where file is the name of a file and filep is an open file pointer.
+# where file is either the name of a file or an open file pointer.
 # The open file pointer must have methods write(), tell(), seek(), and
 # close().
 #
@@ -361,6 +357,12 @@ class Aifc_read:
 	#		file for readframes()
 	# _ssnd_chunk -- instantiation of a chunk class for the SSND chunk
 	# _framesize -- size of one frame in the file
+
+	access _file, _nchannels, _nframes, _sampwidth, _framerate, \
+		  _comptype, _compname, _markers, _soundpos, _version, \
+		  _decomp, _comm_chunk_read, __aifc, _ssnd_seek_needed, \
+		  _ssnd_chunk, _framesize: private
+
 	def initfp(self, file):
 		self._file = file
 		self._version = 0
@@ -524,6 +526,8 @@ class Aifc_read:
 	#
 	# Internal methods.
 	#
+	access *: private
+
 	def _decomp_data(self, data):
 		dummy = self._decomp.SetParam(CL.FRAME_BUFFER_SIZE,
 					      len(data) * 2)
@@ -635,13 +639,17 @@ class Aifc_write:
 	# _datalength -- the size of the audio samples written to the header
 	# _datawritten -- the size of the audio samples actually written
 
+	access _file, _comptype, _compname, _nchannels, _sampwidth, \
+		  _framerate, _nframes, _aifc, _version, _comp, \
+		  _nframeswritten, _datalength, _datawritten: private
+
 	def __init__(self, f):
 		if type(f) == type(''):
 			filename = f
 			f = builtin.open(f, 'w')
 		else:
+			# else, assume it is an open file object already
 			filename = '???'
-		# else, assume it is an open file object already
 		self.initfp(f)
 		if filename[-5:] == '.aiff':
 			self._aifc = 0
@@ -826,6 +834,8 @@ class Aifc_write:
 	#
 	# Internal methods.
 	#
+	access *: private
+
 	def _comp_data(self, data):
 		dum = self._comp.SetParam(CL.FRAME_BUFFER_SIZE, len(data))
 		dum = self._comp.SetParam(CL.COMPRESSED_BUFFER_SIZE, len(data))
@@ -987,6 +997,6 @@ def open(f, mode):
 	elif mode == 'w':
 		return Aifc_write(f)
 	else:
-		raise Error, 'mode must be \'r\' or \'w\''
+		raise Error, "mode must be 'r' or 'w'"
 
 openfp = open # B/W compatibility
diff --git a/Lib/plat-sunos4/SUNAUDIODEV.py b/Lib/plat-sunos4/SUNAUDIODEV.py
index 7e46871f327..b66610d903e 100755
--- a/Lib/plat-sunos4/SUNAUDIODEV.py
+++ b/Lib/plat-sunos4/SUNAUDIODEV.py
@@ -2,15 +2,26 @@
 # The names are the same as in audioio.h with the leading AUDIO_
 # removed.
 
+# Not all values are supported on all releases of SunOS.
+
 # Encoding types, for fields i_encoding and o_encoding
 
-ENCODING_ULAW = 1
-ENCODING_ALAW = 2
+ENCODING_NONE = 0			# no encoding assigned
+ENCODING_ULAW = 1			# u-law encoding
+ENCODING_ALAW = 2			# A-law encoding
+ENCODING_LINEAR = 3			# Linear PCM encoding
 
 # Gain ranges for i_gain, o_gain and monitor_gain
 
-MIN_GAIN = 0
-MAX_GAIN = 255
+MIN_GAIN = 0				# minimum gain value
+MAX_GAIN = 255				# maximum gain value
+
+# Balance values for i_balance and o_balance
+
+LEFT_BALANCE = 0			# left channel only
+MID_BALANCE = 32			# equal left/right channel
+RIGHT_BALANCE = 64			# right channel only
+BALANCE_SHIFT = 3
 
 # Port names for i_port and o_port
 
@@ -19,7 +30,9 @@ PORT_B = 2
 PORT_C = 3
 PORT_D = 4
 
-SPEAKER = PORT_A
-HEADPHONE = PORT_B
+SPEAKER = 0x01				# output to built-in speaker
+HEADPHONE = 0x02			# output to headphone jack
+LINE_OUT = 0x04				# output to line out
 
-MICROPHONE = PORT_A
+MICROPHONE = 0x01			# input from microphone
+LINE_IN = 0x02				# input from line in
diff --git a/Lib/sunau.py b/Lib/sunau.py
index 08e4d208a2a..00c2a28cbbb 100644
--- a/Lib/sunau.py
+++ b/Lib/sunau.py
@@ -37,9 +37,7 @@
 #
 # Reading audio files:
 #	f = au.open(file, 'r')
-# or
-#	f = au.openfp(filep, 'r')
-# where file is the name of a file and filep is an open file pointer.
+# where file is either the name of a file or an open file pointer.
 # The open file pointer must have methods read(), seek(), and close().
 # When the setpos() and rewind() methods are not used, the seek()
 # method is not  necessary.
@@ -72,9 +70,7 @@
 #
 # Writing audio files:
 #	f = au.open(file, 'w')
-# or
-#	f = au.openfp(filep, 'w')
-# where file is the name of a file and filep is an open file pointer.
+# where file is either the name of a file or an open file pointer.
 # The open file pointer must have methods write(), tell(), seek(), and
 # close().
 #
@@ -151,6 +147,20 @@ def _write_u32(file, x):
 		file.write(chr(int(data[i])))
 
 class Au_read:
+	access _file, _soundpos, _hdr_size, _data_size, _encoding, \
+		  _sampwidth, _framesize, _framerate, _nchannels, \
+		  _framesize, _info: private
+
+	def __init__(self, f):
+		if type(f) == type(''):
+			import builtin
+			f = builtin.open(f, 'r')
+		self.initfp(f)
+
+	def __del__(self):
+		if self._file:
+			self.close()
+
 	def initfp(self, file):
 		self._file = file
 		self._soundpos = 0
@@ -193,16 +203,6 @@ class Au_read:
 		else:
 			self._info = ''
 
-	def __init__(self, f):
-		if type(f) == type(''):
-			import builtin
-			f = builtin.open(f, 'r')
-		self.initfp(f)
-
-	def __del__(self):
-		if self._file:
-			self.close()
-
 	def getfp(self):
 		return self._file
 
@@ -278,12 +278,20 @@ class Au_read:
 		self._file = None
 
 class Au_write:
+	access _file, _framerate, _nchannels, _sampwidth, _framesize, \
+		  _nframes, _nframeswritten, _datawritten, _info, \
+		  _comptype: private
+
 	def __init__(self, f):
 		if type(f) == type(''):
 			import builtin
 			f = builtin.open(f, 'w')
 		self.initfp(f)
 
+	def __del__(self):
+		if self._file:
+			self.close()
+
 	def initfp(self, file):
 		self._file = file
 		self._framerate = 0
@@ -297,10 +305,6 @@ class Au_write:
 		self._info = ''
 		self._comptype = 'ULAW'	# default is U-law
 
-	def __del__(self):
-		if self._file:
-			self.close()
-
 	def setnchannels(self, nchannels):
 		if self._nframeswritten:
 			raise Error, 'cannot change parameters after starting to write'
@@ -404,6 +408,8 @@ class Au_write:
 	#
 	# private methods
 	#
+	access *: private
+
 	def _ensure_header_written(self):
 		if not self._nframeswritten:
 			if not self._nchannels:
diff --git a/Lib/sunos4/SUNAUDIODEV.py b/Lib/sunos4/SUNAUDIODEV.py
index 7e46871f327..b66610d903e 100755
--- a/Lib/sunos4/SUNAUDIODEV.py
+++ b/Lib/sunos4/SUNAUDIODEV.py
@@ -2,15 +2,26 @@
 # The names are the same as in audioio.h with the leading AUDIO_
 # removed.
 
+# Not all values are supported on all releases of SunOS.
+
 # Encoding types, for fields i_encoding and o_encoding
 
-ENCODING_ULAW = 1
-ENCODING_ALAW = 2
+ENCODING_NONE = 0			# no encoding assigned
+ENCODING_ULAW = 1			# u-law encoding
+ENCODING_ALAW = 2			# A-law encoding
+ENCODING_LINEAR = 3			# Linear PCM encoding
 
 # Gain ranges for i_gain, o_gain and monitor_gain
 
-MIN_GAIN = 0
-MAX_GAIN = 255
+MIN_GAIN = 0				# minimum gain value
+MAX_GAIN = 255				# maximum gain value
+
+# Balance values for i_balance and o_balance
+
+LEFT_BALANCE = 0			# left channel only
+MID_BALANCE = 32			# equal left/right channel
+RIGHT_BALANCE = 64			# right channel only
+BALANCE_SHIFT = 3
 
 # Port names for i_port and o_port
 
@@ -19,7 +30,9 @@ PORT_B = 2
 PORT_C = 3
 PORT_D = 4
 
-SPEAKER = PORT_A
-HEADPHONE = PORT_B
+SPEAKER = 0x01				# output to built-in speaker
+HEADPHONE = 0x02			# output to headphone jack
+LINE_OUT = 0x04				# output to line out
 
-MICROPHONE = PORT_A
+MICROPHONE = 0x01			# input from microphone
+LINE_IN = 0x02				# input from line in