Finally got around to fixing my DP/4 the other day while listening to this amazing show:  https://www.mixcloud.com/resonanceextra/sm-ll-1-repetition-7th-november-2016/
My DP/4 has produced annoying crackling noises for a long time. Turned out an underdimensioned fuse was broken. Easy fix.
This track is a single patch on the Yamaha FB-01 sequenced by the Octatrack. Outputs from FB-01 goes into mixer with aux sends to Ensoniq DP/4. 
Single-take recording with errors and mistakes as usual.

FB-01, DP/4 Dub

Vialan