i am almost 1.5-1 at 28.400....
so something is wrong with that balun i guess.
Possibly, but not necessarily. A 4 : 1 balun will change the impedance that the
tuner has to match. It is possible that it shifts the impedance out of range,
especially if you have also changed the wire length.
You'll have to test the balun with a 200 ohm load and see what SWR you get.
You can't count on the impedance of the loop inside the building to tell you
anything about the balun.
Even though you can match the antenna, a typical steel and concrete building
can have very high signal attenuation. It isn't surprising that you can't hear
signals very well, even if the band is open.
At an SWR of 1.5:1 you are only losing %4 of your Forward Power
While I agree that an SWR of 1.5 : 1 is nothing to worry about, the assumption
that it represents a loss of 4% of power is inaccurate and misleading. You can't
equate reflected power with power lost in spite of the number of such tables
prepared for CBers over the years.