Apologies for the delayed reply.
I’ve never heard of this issue to be honest, but if Syphon is taking a second to record it certainly sounds like an issue.
* What operating system and machine are you on?
* Do you have any additional audio hardware like capture devices?
* What bitrate audio are you recording?
* What bitrate video are you recording? (resolution and frame rate)
* What type of disk are you using?
* Ensure you are on the latest versions of Soundflower
Ensure that your drive is fast enough, and that you are using a ‘normal’ bitrate around 44.1 or 44.8 Khz, and you are using a per frame or no compression like Photo JPEG, Uncompressed, Pro Res. Avoid h.264. Same for audio, use LinearPCM. Those options tend to use more disk space, and require faster disks, but give you better results.
Im unsure where the second or so delay is coming from. Let us know if the above is helpful.