Since I updated my two Foscam FI8905W to the latest firmware (Firmware Version: 11.35.2.56 / Embeded Web UI Version: 2.4.20.10)
I have this error, at random: No signal I/O error: 0
Sometimes the web interface of the cameras is not responding, sometime it does...
Which version of Blue Iris are you on? The version released today, 3.52.00 has this fix it it, which might apply.
"Updates to RTCP code which will keep some devices from dropping the stream, causing occasional pauses in the video."