I had posted this issue about a week ago and resolved it. Now I am back with the same issue. I am using the presonus audiobox 44vsl into sonar. I have signal in the led's in the vsl mixer and can hear my signal in my headphones which are plugged to the audiobox. However no input signa to my armed track in sonar. Settings in sonar are; driver mode: asio, playback timing master: audiobox asio driver line out one, record timing master: audiobox asio driver mic/instr 1. Under "Devices"; Input Drivers: audiobox asio driver mic/instr 1 and audiobox asio driver mic/instr 3 are checked, Output Drivers: audiobox asio driver line out 1 and audiobox asio driver line out 3 are checked. This had worked last week. I went out of town to work. Cme back today and fired everything up. Had buzzing in my signal. Changed cables and guitar with no change. Updated drivers for audiobox via presonus website (as well as firmware) and finally got clean sound and signal at vsl. However this is when I lost signal to sonar. I have tried every input option available under the inputs on the armed track. I switched back to MME drivers. Restarted sonar then switched back to asio and restarted sonar keeping the stated settings. I have rebooted my laptop between major changes as well. I am stumped, yet again. I've been over the presonus manual. Maybe it is something I am missing.

Have you tried using the Wave Profiler? I had a similar issue with my 44vsl and everything started working again after I reran the Profiler. FWIW, I switched to WDM driver mode as I wasn't able to get ASIO to consistently work with Sonar. I haven't had any trouble since.

Regards,
Dan

Do you have more than one audio device or a USB microphone? If so, then switch to WDM mode (not MME) and run the Wave Profiler. ASIO mode can only use one audio device at a time. You should also disable the onboard soundchip in your computer or at least make sure its not selected in Audio Preferences.