--- In logic-users@yahoogroups.com, "Trevor Gilchrist" <trevor@...> wrote: > IAC only has one bus. But it's a two-ended bus, not just a source or destination. Logic will also receive anything sent to it (Logic listens to all ports), so if the sending instrument is the selected track in the Arrange, you have a loop. Block the IAC port outlet at the environment Physical Input (cable to dead-end monitor or such). This will prevent messages from the IAC bus reaching the Arrange. Note that if you're using Logic Express, you're screwed - there's no way to block one port. In this case, MIDIPipe should be used rather than IAC. John Pitcairn ---------------------------------------------------------------------------- - LC Xmu Logic/Mackie Control emulation & management, LC Xview software LC/MC display, Logic environments & stuff... Opus Locus - http://www.opuslocus.com ---------------------------------------------------------------------------- -