Incorrect volume readings

Upon detailed investigation on studies that have "update on every tick" enabled, it appears the first tick used by the study in a new minute carries over the total volume of the previous minute no matter how far it's in the new 1 minute period. During a quiet region, I noticed the first tick arrive around 30 seconds into the minute but it still had the volume set to that of the previous minute. This looks like a bug, right? I've discovered this once I printed out currenttime_s to observe the real-time values. Can anyone confirm this please? If true, then I can't trust the volume associated with the first tick for each 1 minute bar in real-time. This is a critical issue for my studies. What I could do is ignore the first tick and read the volume off the second one. However, I shouldn't have to do this, unless I doing something wrong. Am I?