Hey, I'm late to the party.
How big is the dip in your hearing at 1k? I wouldn't automatically worry about that just becaue you see it in a test.
For one, your brain is compensating for it. But mainly, it's normal for your ears not to be totally flat and not identical.
Everyone over, I dunno, 40 is going to have some loss between 4-8kHz. And I'm going to guess that your hearing above 8kHz isn't linear, even though standard hearing tests don't go that high. Last time I checked, I could hear a 20kHz sine wave (if it's loud enough), but I can't hear 14kHz.