Two things are at play here... First is when you have a recording over 30 minutes, the conversion to WAV or MP3 takes exponentially longer, a 60 minute recording might take 45-120 minutes to re-encode for emailing, I have seen recordings around 2 hours take 4+ hours. The second is the attachment size allowed on the email server, both sending and receiving servers.
We started limiting any recording on a system without a PS-1 to 45 minutes, and 90 minutes on systems with a PS-1.
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