Duplication of blocks from flying machines

I know this has been a bug for a while but It has gotten worse with the updates and snapshots... I was trying to make an elevator using the new observer blocks ... the only downside is that when the elevator tends to create ghost blocks. :0 . These ghost blocks disappear when you right click them but its still pretty annoying none the less...
( For those who this may concern... Tech info: Java Version 1.8.6 OS: Windows 10 Home 64-bit Processor: AMD A6-7310 APU with Radeon R4 Graphics @ 2.00 GHz Ram: 4 GB (yes, only 4 ) Thank you... )