Ive had the Qn90B for about a week and noticed some slight local dimming issues when watching 4k blu rays with HDR. Ive noticed slight dimming fluctuations and delays in darker scenes. Also sometimes in transitions from brighter to darker scenes. Ive tested multiple movies, and the problem either doesn’t occur or is less apparent in live action movies. So far, I’ve only noticed the issue across multiple animated 4k blu rays. The issue isn’t persistent (not all dark scenes), but it does happen occasionally. The issue occurs on all local dimming settings (low,standard,high). I tested one of the discs with more problematic scenes across multiple platforms (standard blu ray, streaming) and the issues either did not occur or were less severe. The issue seems more apparent to me on 4k discs with hdr (although I haven’t viewed much streaming content yet). I know it isn’t the disc itself as i tested it with the same 4k player on 3 samsung tvs and only saw the fluctuations on the Qn90B. So I’m assuming the local dimming algorithm could possibly use some slight tweaks in a future software update.