diff --git a/src/PortAudio.jl b/src/PortAudio.jl
index 1326b26..2bba706 100644
--- a/src/PortAudio.jl
+++ b/src/PortAudio.jl
@@ -4,6 +4,7 @@ module PortAudio
 
 using SampleTypes
 using Devectorize
+using RingBuffers
 
 # Get binary dependencies loaded from BinDeps
 include( "../deps/deps.jl")
@@ -102,8 +103,10 @@ type PortAudioStream{T, U}
             Ref(Pa_StreamParameters(outdev.idx, outchans, type_to_fmt[T], 0.0, C_NULL))
         this = new(sr, bufsize, C_NULL)
         finalizer(this, close)
-        this.sink = PortAudioSink{T, U}(outdev.name, this, outchans, bufsize)
-        this.source = PortAudioSource{T, U}(indev.name, this, inchans, bufsize)
+        this.sink = PortAudioSink{T, U}(outdev.name, this, outchans, bufsize;
+                                        prefill=false, underflow=PAD)
+        this.source = PortAudioSource{T, U}(indev.name, this, inchans, bufsize;
+                                            prefill=true, overflow=OVERWRITE)
         this.taskwork = Base.SingleAsyncWork(_ -> wakeaudiotask(this))
         this.taskcond = Condition()
         this.bufstate = PortAudioPending
@@ -183,16 +186,20 @@ for (TypeName, Super) in ((:PortAudioSink, :SampleSink),
     @eval type $TypeName{T, U} <: $Super
         name::UTF8String
         stream::PortAudioStream{T, U}
-        waiters::Vector{Condition}
         jlbuf::Array{T, 2}
         pabuf::Array{T, 2}
+        ringbuf::RingBuffer{T}
 
-        function $TypeName(name, stream, channels, bufsize)
+        function $TypeName(name, stream, channels, bufsize; prefill=false, ringbuf_args...)
             # portaudio data comes in interleaved, so we'll end up transposing
             # it back and forth to julia column-major
             jlbuf = zeros(T, bufsize, channels)
             pabuf = zeros(T, channels, bufsize)
-            new(name, stream, Condition[], jlbuf, pabuf)
+            ringbuf = RingBuffer(T, bufsize, channels; ringbuf_args...)
+            if prefill
+                write(ringbuf, zeros(T, bufsize, channels))
+            end
+            new(name, stream, jlbuf, pabuf, ringbuf)
         end
     end
 end
@@ -207,53 +214,11 @@ SampleTypes.samplerate(s::Union{PortAudioSink, PortAudioSource}) = samplerate(s.
 Base.eltype{T, U}(::Union{PortAudioSink{T, U}, PortAudioSource{T, U}}) = T
 
 function SampleTypes.unsafe_write(sink::PortAudioSink, buf::SampleBuf)
-    c = Condition()
-    push!(sink.waiters, c)
-
-    total = nframes(buf)
-    written = 0
-    try
-        while written < total
-            donecond = wait(c)
-            n = min(size(sink.jlbuf, 1), total-written)
-            bufstart = 1+written
-            bufend = n+written
-            @devec sink.jlbuf[1:n, :] = buf[bufstart:bufend, :]
-            written += n
-            notify(donecond)
-        end
-    finally
-        # make sure we remove our condition even if the user ctrl-C'ed out
-        shift!(sink.waiters)
-    end
-
-    written
+    write(sink.ringbuf, buf)
 end
 
 function SampleTypes.unsafe_read!(source::PortAudioSource, buf::SampleBuf)
-    c = Condition()
-    push!(source.waiters, c)
-
-    total = nframes(buf)
-    read = 0
-
-    try
-        while read < total
-            # we'll get woken up when the next data comes in
-            donecond = wait(c)
-            n = min(size(source.jlbuf, 1), total-read)
-            bufstart = 1+read
-            bufend = n+read
-            @devec buf[bufstart:bufend, :] = source.jlbuf[1:n, :]
-            read += n
-            notify(donecond)
-        end
-    finally
-        # make sure we remove our condition even if the user ctrl-C'ed out
-        shift!(source.waiters)
-    end
-
-    read
+    read!(source.ringbuf, buf)
 end
 
 # This is the callback function that gets called directly in the PortAudio
@@ -282,7 +247,6 @@ end
 wakeaudiotask(stream::PortAudioStream) = notify(stream.taskcond)
 
 function audiotask{T, U}(stream::PortAudioStream{T, U})
-    donecond = Condition()
     while true
         try
             wait(stream.taskcond)
@@ -291,35 +255,26 @@ function audiotask{T, U}(stream::PortAudioStream{T, U})
                 continue
             end
 
-            # we notify the source waiters (readers) first so that if there's a loop
-            # it will be able to feed back to the writers
-            if length(stream.source.waiters) > 0
-                transpose!(stream.source.jlbuf, stream.source.pabuf)
-                notify(stream.source.waiters[1], donecond)
-                wait(donecond)
-            end
-            if length(stream.sink.waiters) > 0
-                notify(stream.sink.waiters[1], donecond)
-                wait(donecond)
-                transpose!(stream.sink.pabuf, stream.sink.jlbuf)
-            else
-                fill!(stream.sink.pabuf, zero(T))
-            end
+            transpose!(stream.source.jlbuf, stream.source.pabuf)
+            write(stream.source.ringbuf, stream.source.jlbuf)
+
+            read!(stream.sink.ringbuf, stream.sink.jlbuf)
+            transpose!(stream.sink.pabuf, stream.sink.jlbuf)
 
             stream.bufstate = PortAudioPending
         catch ex
-            if isa(ex, InterruptException)
-                for w in stream.source.waiters
-                    notify(w, ex; error=true)
-                end
-                for w in stream.sink.waiters
-                    notify(w, ex; error=true)
-                end
-            else
-                warn("Audio Task died with exception: $ex")
-                Base.show_backtrace(STDOUT, catch_backtrace())
-                break
-            end
+            # if isa(ex, InterruptException)
+            #     for w in stream.source.waiters
+            #         notify(w, ex; error=true)
+            #     end
+            #     for w in stream.sink.waiters
+            #         notify(w, ex; error=true)
+            #     end
+            # else
+            warn("Audio Task died with exception: $ex")
+            Base.show_backtrace(STDOUT, catch_backtrace())
+            break
+            # end
         end
     end
 end