I have a Sony Bravia HDTV with 4 HDMI ports and Bose 321 DVD Series III with HDMI and up-convert capability. Right now the only connection I have between the two units is HDMI. Am I getting the best sound possible including "faux" surround sound with the 2 Bose arrays or do I need to add an optical between the two units in addition to the HDMI connection? Thanks.