diff --git a/include/media/nbaio/NBAIO.h b/include/media/nbaio/NBAIO.h
index 5278bf8..be0c15b 100644
--- a/include/media/nbaio/NBAIO.h
+++ b/include/media/nbaio/NBAIO.h
@@ -54,11 +54,12 @@
 // too large, then this decision should be re-visited.
 // Sample rate and channel count are explicit, PCM interleaved 16-bit is assumed.
 struct NBAIO_Format {
+// FIXME make this a class, and change Format_... global methods to class methods
 //private:
     unsigned    mSampleRate;
     unsigned    mChannelCount;
     audio_format_t  mFormat;
-    ssize_t     mFrameSize;
+    size_t      mFrameSize;
 };
 
 extern const NBAIO_Format Format_Invalid;
diff --git a/media/libnbaio/NBAIO.cpp b/media/libnbaio/NBAIO.cpp
index a669fbb..ff3284c 100644
--- a/media/libnbaio/NBAIO.cpp
+++ b/media/libnbaio/NBAIO.cpp
@@ -27,16 +27,6 @@
     return format.mFrameSize;
 }
 
-#if 0
-int Format_frameBitShift(const NBAIO_Format& format)
-{
-    // FIXME The sample format is hard-coded to AUDIO_FORMAT_PCM_16_BIT
-    // sizeof(short) == 2, so frame size == 1 << channels
-    return Format_channelCount(format);
-    // FIXME must return -1 for non-power of 2
-}
-#endif
-
 const NBAIO_Format Format_Invalid = { 0, 0, AUDIO_FORMAT_INVALID, 0 };
 
 unsigned Format_sampleRate(const NBAIO_Format& format)