TMS320C6678: H264 Encoder configuration issues

Part Number:TMS320C6678

Hi

I'm trying to configure the H264 encoder on the C6678 for low bitrate operation.

using the latest version (1.0.3)

My video resolution is 320x240, very simple image, no motion.

configured for 50kbps

I've tried both CBR and VBR but the result is always the same -> outputting close to 250kbps regardless of my setting of rcalgo, targetbitrate, ratecontrol preset, initial QI , initial QP. 

1. is there a newer version of this encoder (1.0.3 is from 2015)?

2. Does this encoder support low bitrates (sub 64kbps)?

3. is there some other parameter that I might be missing?

Thanks