The issue is that 9.4 and above which
requires configuring custom ciphers in order to user third party CA certs for
Anyconnect.
ssl cipher tlsv1.2 custom
"AES256-SHA:AES128-SHA:DHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA:DES-CBC3-SHA:DES-CBC-SHA:RC4-SHA:RC4-MD5"
Here’s the 9.4 release notes
that detail the issue - http://www.cisco.com/c/en/us/td/docs/security/asa/asa94/release/notes/asarn94.html