ROC Chrono Malfunction - any ideas why/how?

[srvrf]

As I have posted, I just picked up an AP ROC 25860 and love it. The only problem I found out after I had completed my Daytona trade is that the minute hand on the chrono register does not advance past the first minute (everything works perfectly until 1 min, 59 seconds. Then the seconds hand of the chrono passes 12:00 and keeps going as it should, but the minute hand doesn't advance to "2" or any further). I checked it for about a minute and a half in the store so it appeared the chrono worked as it should. Now the dealer is dealing with it and will of course fix it, so that's not the problem. Not knowing that much about the drive of the chrono in these watches, I was wondering if anyone had ideas of what is going on or if they have had similar experiences?

Thanks,

Steve