Is is possible to get video going through a FreeSWITCH SBS where one side is using SRTP and the other RTP?

I suspect the answer is no, as it requires proxy_media=true to be set, although I could be wrong.

When I try with proxy_media=true, I always get a:

415 Unsupported Media Type

Note that I have all the appropriate codec enabled on the FS servers and the SIP clients.

Thanks

Peter