Default LHDC V5 ABR bitrate selection is just bad. Min is 128 kbps, which really destroys audio quality, so change bitrate tables to the following:
static uint32_t auto_bitrate_adjust_table_lhdcv5_44k[] = {240, 320, 400, 400, 500, 500, 900};
static uint32_t auto_bitrate_adjust_table_lhdcv5_48k[] = {256, 320, 400, 400, 500, 500, 900};
static uint32_t auto_bitrate_adjust_table_lhdcv5_96k[] = {256, 320, 400, 400, 500, 900, 1000};
static uint32_t auto_bitrate_adjust_table_lhdcv5_192k[] = {256, 320, 400, 400, 500, 900, 1000};