I’m looking into designing a product that involves VoIP and I haven’t had much luck finding a good codec that offers a low data rate. The lowest I have seen is the 16k ADPCM, but I’d like to go lower than that. 5.3/6.3k would be nice. Any tips? I’d like to avoid a DSP because it seems like the prices are sky-high, and the patent fees are expensive as well. We’re looking at about 100 units annually, so it would be nice to find a supplier that can provide quantities that small.