Hi,
My Virus TI has been working great until I purchased a new MBP running Mavericks 10.9.4.
Upon setting up the new Mac I installed the latest 5.1.1 (2) update. I hadn't really used the Virus with the Mac previously. After the update everything seemed fine until I began to create complex patches with automation within Ableton 9.1.6 (both 32 & 64 bit). Within about 1 to 10 minutes the Virus would begin to emit an uninterrupted unpleasant pulse-wave sounding noise on all outputs - usb, audio and headphones. The odd numbered parts become unresponsive but even numbered parts continue to function and output audio together with the buzzing sound. Virus Control remains responsive. After shutting down the Virus the LFO LEDs remain on. I also encountered the problem of not being able to see my personal library and having constant synchronisation issues.
I assumed that this problem was because of the update, so reverted back to 5.0.8. However the problem still occurs, with the added problem of occasionally encountering corrupted sounding (bit/sample rate reduced) audio via the USB, or losing audio altogether accompanied by a completely unresponsive TI unit (power cable has to be removed to reboot). I have tried different USB ports, cables, and also USB2 inputs of Thunderbolt Display, plus a USB Hub (not the Belkin), to no avail. I also run at 44.1 kHz.
In contrast, the Virus TI with my original Windows 7 workstation continues to function more or less perfectly as far as I can tell, with no DSP crashes and great sound and synchronisation via USB. So it seems to me that this is (hopefully) not a Virus hardware problem.
The crash seems to happen when I use the Formant Complex Oscillators, with the simultaneous automation of the F-Shift, F-Spread, Wavetable Index, combined with simultaneous automation of the Comb Filter Frequency. Using complex modulations and LFO's to control these parameters has ( I think - from memory) produced a crash but seems more stable than automation, though I have only done limited testing. It also appears to function fine when using MIDI control, but automation of the Filterbank and other parameters is complicated so I haven't fully tested that functionality either.
Anyone ideas would be appreciated.
Thanks
P