HDMI not permitted on device using Mini's A/V Output

Use Mini hooked up to large TV via HDMI and also hardwired to small bedside DVD player (which I use as a mpnitor) via the Mini's A/V output. Occasionally when watching on DVD player only, I will get the "HDMI not Permitted Banner". I can stop this banner by turning on large TV for approx 30 seconds simultaneously with the DVD player, then turning off large TV, which clears the banner on the DVD player. I watch this small DVD player when wife is sleeping, so turning on large TV sort of defeats the purpose.



Any ideas how to eliminate the warning?