NM_LREAR
chancfg_t ch_lsurr_4 = { (1 << 2), NM_LREAR, 0 };
chancfg_t ch_lsurr_5 = { CH_LSURR, NM_LREAR, 0 };
chancfg_t ch_lrear_7 = { CH_LREAR, NM_LREAR, 0 };