Yeah, I am regretting even listing (2) above as an option to re-route the "Part Output" on all the Parts to "AssignL&R" so that the OP could keep the current backing track setup & increase the volume without having to lower the volumes of each of the Parts, as it is a really bad option since it would strip away the system & master effects from all Parts, which would not be a good thing to do...

Yeah, I am regretting even listing (2) above as an option

No need to do that. IMO your post listing all possible options is EXACTLY the right first step (and the step typically missing) to take when trying to solve a problem. Frankly doing that suggests to me that you are a critical thinker that follows the time-proven problem solving methodology:

First - you list all possible options - without regard to cost, time to implement, practicality, resources needed, etc

Second - you prioritize them based on currently know requirements and parameters. Typically this is when you discover that you need more info about some of the requirements.

Third - gather whatever missing info you can

Fourth - review the prioritized list and note each items advantages and disavantages as a 'solution' and to see if it is complete enough to make a decision

My point being - you NEVER take ANY option off the list - you just move it closer to the bottom.

What you wind up with is a document that not only recommends a particular solution but allows an independent reviewer to know just why that solution was recommended over the others.

as it is a really bad option since it would strip away the system & master effects from all Parts, which would not be a good thing to do...

My comment on that would be that I don't think we even know yet the full details of OPs use case. They may not be using, or even care about, those effects. If so, that might be the perfect solution for OP.

That is exactly why you never remove an option from the list. As new info comes in (or as OP tells us more) it may be that option needs to be moved back up the list ahead of some of the others. It needs to be on the list (perhaps at the bottom) to be able to do that. Otherwise other people reading the list won't even know it was considered.

Sorry for the length but I wanted to commend you for making the list to begin with. Don't regret putting something ON a list - the regrets are for NOT adding possibilities. 

Another "missing" option is using an iPad or similar device connected to the USB TO HOST port and sending the backing track through Digital L&R (USB) from the tablet/external device.  Here the routing options are limited compared to the audio (analog) inputs but still an option.   I already carry a tablet on the gig with me so there wouldn't be a penalty in terms of number of devices to carry but it may impact some.

Posted by: Jason

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Another "missing" option is using an iPad or similar device connected to the USB TO HOST port and sending the backing track through Digital L&R (USB) from the tablet/external device.  Here the routing options are limited compared to the audio (analog) inputs but still an option.   I already carry a tablet on the gig with me so there wouldn't be a penalty in terms of number of devices to carry but it may impact some.

 

Just add your backing track files to each of your performances in a Live Set and play them with the push of a button (two pushes gets you real-time volume and playback position controls). Much simpler than all that external playback complexity, IMHO.