add_with_wraparound
add_with_wraparound(ua, &ua->rate_feedback_start, 1);
add_with_wraparound(ua, &write_ptr, ua->rate_feedback_count);
add_with_wraparound(ua, &ua->rate_feedback_start, 1);
add_with_wraparound(ua, &ua->rate_feedback_start, 1);