code: @Override
      public boolean addData(IoBuffer data) {
          if (data.hasRemaining()) {
              // mark
              int start = data.position();
              // ensure we are at the beginning
              data.rewind();
              byte frameType = data.get();
              log.trace("Frame type: {}", frameType);
              byte header = data.get();
              // if we don't have the AACDecoderConfigurationRecord stored
              if (blockDataAACDCR == null) {
                  if ((((frameType & 0xf0) >> 4) == AudioCodec.AAC.getId()) && (header == 0)) {
                      // back to the beginning
                      data.rewind();
                      blockDataAACDCR = new byte[data.remaining()];
                      data.get(blockDataAACDCR);
                  }
              }
              data.position(start);
          }
          return true;
      }
docs: {@inheritDoc}