Panasonic AJ-HD1200Ap deck channel condition lamps

Trying to master to HD tape from FCP DVCPro HD 720p60 timeline (23.98 fps) using AJ-HD1200Ap deck. Channel Condition lamps remain green during recording, but flash to white and sometimes red during playback and sometimes (but not always) picture clearly deteriorates. Problem is most evident when playing back HD720p60 bars! Have tried cleaning heads, multiple tapes, but same scenes continue to trigger the white and red lamps (especially color bars) during playback. The lamps seem to trigger only on scenes near (but below) 100% IRE on waveform. If I apply a color correction filter and drop the brightest highlights to 90% or below (even on bars), the lamps stay green. Has anyone ever seen this? Have used this deck for more than a year and never had this problem before.