Corrected entry: When "Desert Camo" SG-1 returns to their dimension through the Stargate, we hear 5 "slurps" indicating someone passing through the gate, however there are only 4 members on the team.
Corrected entry: Sgt Walter Harriman shouts "Unauthorized offworld activation" instead of "Unscheduled offworld activation". "Unauthorized" is only for outgoing wormholes, and makes no sense in this context. It is unlikely to be a character mistake as he generally says "unscheduled" two or three times per episode.
Correction: Why could this not be a character mistake? People sometimes say the wrong thing inadvertently, so this actually makes Walter appear for "real" in a sense, so this would not be a production mistake.
Correction: The 5th sound effect could have been the rather large carrying case (contains the cure for the Ori plague) that Janet was given by Sam. Objects have been shown to make that same sound when the hit the event horizon.