This amp does take some time to break in, but the volume issue is a little strange. At 12 o'clock it should play very loud with 88dB/W/m speakers (like the ones you have).
Assuming all the connections are correct, the next place I'd look would be the input. What source do you use? If it's a TT, is the right phono input selected (the MM/MC switch on the back?) If it's another source, does it have a proper output level? If you have any other components connected to the tape or preamp outs, try and disconnect them and see if it helps.
At any rate, this does not look normal. You should probably contact the vendor.
Assuming all the connections are correct, the next place I'd look would be the input. What source do you use? If it's a TT, is the right phono input selected (the MM/MC switch on the back?) If it's another source, does it have a proper output level? If you have any other components connected to the tape or preamp outs, try and disconnect them and see if it helps.
At any rate, this does not look normal. You should probably contact the vendor.