I'm doing something a little bit different with this post, and actually talking about two songs in the same post. There's a reason I'm doing this, though, and hopefully after you've heard them both back to back that reason will be obvious.
As I've said before, Ultravox is often credited by the music press, fans, and wikipedia with having the first true synthpop song ever recorded, "Hiroshima Mon Amour" in 1977 and the first true synthpop album ever recorded, Systems of Romance in 1978. After that happened, John Foxx, frontman and one of the leading creative sides to the band, left to pursue his solo career, starting with 1980's release Metamatic, 1981's The Garden, etc. Ultravox, after recruiting Midge Ure, whom band member Billy Currie had met on the Visage project back in '78 and '79 (it took a little while to sign to Polydor and release Visage, which also came out in 1980) released Vienna in 1980 as well.
This weird nepotistic relationship between Foxx, Ultravox and Visage was kind of odd in that both Foxx and Ure have sung tracks that they worked on from some of those other groups, especially in live sets. Foxx wrote a song called "Systems of Romance" that was originally intended to slate onto the Ultravox album of the same name, but which didn't get recorded until his 1982 solo album The Garden. He also used some tracks that were performed with Ultravox (while he was still a member of that band) but never recorded by them, "He's a Liquid" and "Touch and Go." In one interview in the late '90s, Warren Cann, drummer for Ultravox up until 1985 or so, noted that he considered those songs Ultravox songs, not Foxx solo songs, and remarked that Ultravox was not credited when they were included on Foxx's Metamatic.
That said, have a listen to Ultravox's "Mr. X" after you've listened to "Touch and Go." Foxx wasn't credited on that one either. So, who wrote that main synth line, I wonder?