Only 2 VI per instrument track?

[pjmusiced]

In the past I have had no issues with running 8-16 Kontakt instruments through a single Instrument track. For some reason I can now only have 2 VIs play through a single instrument track. I can see signal coming from a third VI (and I can record MID data onto the track) but no sound is coming out of the speakers.

So far, I've updated PT to the current version, I reinstalled the driver. I've tried different Playback engines (ASIO4ALL v2 and Mbox) and defaulted the input and outputs on my I/O.

I am out of ideas on how to fix this and wonder if this is the correct forum for this question. Thanks in advance.



Pro Tools: Studio Version
Interface: Mbox (3rd Generation)
MIDI Controller: NI Komplete Kontrol A25 and M-Audio ProKeys 88

Processor Intel(R) Core(TM) i7-4770K CPU @ 3.50GHz 3.50 GHz
Installed RAM 16.0 GB
System type 64-bit operating system, x64-based processor
Edition Windows 10 Home
Version 21H1
Experience Windows Feature Experience Pack 120.2212.4180.0