When a server has been to sleep than, after it wakes up, sync may be unreliable for a period.

The server tracks the difference between each player's internal clock (called jiffies) and real time from the server's viewpoint. For each player this is known as the jiffiesEpoch. Tracking occurs on each status response from the player: every 5s while idle and every 1s while playing. A hysteresis-type algorithm is used to reduce jitter so that apparent clock drift caused by short-term network congestion or unusual latency is not over-compensated for. This algorithm does not allow for the possibility that a player's clock may drift for an extended period without SC being informed, such as may happen when when the SC server goes into suspend or hibernate modes.

If the unobserved drift has been in one direction (either fast or slow) then the correction will be immediate. In the other direction, and error of less that 50s will only be corrected at a rate of 5ms/correction (every 8s while playing or every 50s while idle). Even when playing, this could theoretically take  up to 22 hours to correct, although it is unlikely that the Squeezebox clock drift would have been so large; probably at most a second or two a SB clock drift is typically around 1ms/minute.