Qi Mei 28-hole quality problems

Good, Keith. And close the reed gap.

I complained with the seller and he gave me this explanation, does that make any sence?:

As for your voice is very low, it is because it is an accent harmonica.
Maybe you used a polyphonic harmonica before.
The difference between polyphony and accent of harmonica is as follows:

1. Different effects: Accent harmonica is more suitable for band playing, while polyphonic harmonica is more suitable for solo, ensemble or singing.
2. Difference in timbre: The accented harmonica has a thick, deep and slightly muddy tone, while the polyphonic harmonica is clearer and brighter. The reeds of the upper and lower grids have the same tone, but slightly different in tone quality, thus producing a special trill.
3. The difference is that the tones of the two reeds are different, but there is an octave difference. The timbre of accented harmonica is also different from that of polyphonic harmonica. The accented harmonica is elegant and thick, which is suitable for duet, trio, quartet and even grand ensemble with polyphonic harmonica.

The accented harmonica has a deep and soft tone, but it is laborious.

All my stuff is done on a Qi Meo 10 hole chromatic harmonica and I have not had much trouble with it. I sometimes get a sticky G probably due to saliva which I fix by giving it a bath. It was not an expensive harmonica and use if every day.

You take the outside cover plates off. look at the reeds and see how far they are out of the hole. If they are too far out the reed won’t sound with soft breath. If inside  the hole they won’t play. So it takes a bit of pushing the reed gently till it is just out of the hole. Carful not to go too far. this is for draw notes. For blow notes its best to unscrew the plate the reeds are on to adjust the reed. Although experienced people can use a tool to adjust reeds without removing the plate. Adjusting the gap at the hole by bending the reed determines the playability of the reed. It’s trial and error. If you are new to it all just give it a go and learn.

The trick to reed gapping is to get all the reed in the slot at once. Push on the tip to test. If different parts of the reed enter the slot at different times then you need to "profile" the reed. At rest there should be a slight upward curve to the reed. As you push it into the slot it will straighten. Try for a gap about the thickness of the reed tip. Lower notes get a little more gap.

I have an inexpensive Chinese tremolo harmonica with similar deep tuning marks on all the reeds. I suspect those reed plates started out as a different key. Mine plays ok now after I did hours of work on it, but it still is not as good as my Suzuki tremolo harps.