In OS 4.0a on Ketron X4 (probably also on X1) it is definitely for sure BUG in Output assignment modes L&R+3 and L&R+3&4.

If Delay, Chorus and Distorsion effects shouldn't be operative on main L&R outputs while additional outputs are used dry, then why they can be heard in some particular cases? They should work or they shouldn't work.

It is definitely BUG, so I cannot replace the unit to solve the problem.
Although X1/X4 are older products, Ketron must release new OS, or pull units back and replace with XD3 with price difference back.
Product is bought as new, via authorised dealer in Croatia.

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