Midi Timing Issues - Logic 6.4 On G4 With Jv1080 Options

[bradders]

Hi
I need some help. First of all i am not vastly experienced with Logic.

I'm running logic pro 6.4 on my G4 with a jv1080 connected with a 2x2 midisport usb using the latest drivers.
I do quite a lot of arranging and often have several midi tracks running at once (often the full 16). I usually enter each track using the matrix editor and quantize them afterwards.

The problem I have is when i play back the song. There is often a lot of time delays and the problem is worse the more midi tracks I use. It's as if logic can't cope dealing with so many midi commands simultaneously. If I mute some tracks the timing improves. But anything above 2 or 3 tracks starts to cause some timing problems. Surely my G4 is powerful enough to deal with this. Atari managed it decades ago.

I suspect that it's a setting somewhere on the JV. But I haven't got a clue with this machine. It's got a techno sound card inside of which some of the sounds are sampled loops. When I play these sounds without the G4 on they work fine but when i play them with the sound selected from within logic the different elements of the sampled loop seem to play out of sync with one another. I don't know if this problem is related but thought I'd mention it just in case.

It's as if logic is somehow affecting the JV in some way at least.

Look forward to a response from someone with the knowledge.

Cheers
Brad

[lepetitmartien]

Are the pieces really busy with notes?
Are you sure the midisport sends/received a clean MIDI signal?
Are there other USB peripherals save keyboard/mouse/logic key?
How is the midisport attached to the mac? Directly, thru a hub… ?