MAX_CHANNELS
# define MAX_CHANNELS(x) (((x) & 0x7) << 0)
# define MAX_CHANNELS(x) (((x) & 0x7) << 0)
# define MAX_CHANNELS(x) (((x) & 0x7) << 0)
# define MAX_CHANNELS(x) (((x) & 0x7) << 0)
#define MAX_CHANNELS 3
#define MAX_CHANNELS 4