In 9.5, I get 0 when I check user delay/ping for External FX. The audio signal is passing through fine. It even sends the ping signal fine (it shows up on the AD converter post-round trip), but it just can’t calculate the delay. 9.0 using the same setup pings fine.
Update: 9.5 pings fine when set to 32 bit processing. In 64 bit mode, ping is broken, which makes me very suspicious about the basic integrity of delay compensation generally in 64 bit.
Windows 10 64 bit