rosbag doesn't playback at same speed

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Turned out to be a decompression issue. I had compressed bags that were unable to decompress and play at the desired frequency of the messages. Using rosbag decompress on these before playing them does the trick.

I didn't initially know of the decompress tool in rosbag so I was re recording the messages (at the slow speed) into another bag and playing that. But that seemed to do some unnatural behavior. Firstly the bags were much longer (which makes sense due to the slow speed) but then using the --clock option didn't make them use the time that was on the messages. They would still use the computer time.