REservation Entries and Item Tracking

We have a strange problem. Nav2009 RTC.

On certain items which have item tracking turned on, and Order Tracking turned on, we sometimes receive a problem whereby the reservation entries for the item tracking appear to have split into decimals, thereby rather than 1 we have 0.6545. Has anyone seen this issue before, we believe it might have something to do with the order tracking being turned on, but we cannot prove this.

Any ideas/help would be much appreciated.