What you could be experiencing are the buffers in the signal path that you may not be used to. Only way to remove them from the signal chain is putting the H90 in Relay bypass mode in the System Menu and removing your analog effects from the inserts, as I/O 3&4 are always on buffered I/Os. Try placing your comp and drive pedals before the H90 and set the H90 to Relay bypass mode to see if it makes a difference. Many people describe the reemergence of high frequency information from the use of buffers as sounding “digital,” when in reality buffers make up for impedance imperfections in the signal chain.
It would be nice if a future update allowed access to insert loop pedals when the H90 is completely bypassed.
If you require the loops to stay open when both presets are bypassed, you can either bypass A and B in PERFORM mode or program an aux switch or MIDI controller to A act/byp and B act/byp simultaneously with one press.
