Since you have not provided a single clue as to what you are using to listen with (the word vinyl by itself doesn't help very much) I am at a loss as to what could cause your problem.

I'll guess anyway. Defective phono cartridge?

check all your connections - undo them and reconnect.  Also make sure the polarity is correct.  Do you know about that?  i.e., make all connections consistent - for instance, if you have the gold wire go to the red terminal and the silver wire to the black terminal, make sure that is the case for each point of connection (at the amp, at the speakers, etc)

Are you haveing to turn it to 2 o'clock to get reasonable volume?

I'm betting on 2 things, you're not using a phono preamp or your phono preamp isn't working correctly, AND as has been offered, you are having a polarity issue.  Polarity issues being REALLY audible USUALLY require a high enough quality system for phase correctness across most of the listening spectrum, starting with the azimuth of the phono pickup/tape head (obviously not an issue with digital assuming a modern dac) and going all the way through the chain to the phase and time alignment of your speaker drivers.  On a crappy system, including expensive crappy system, you can swap speaker polarity all day and never hear a difference.  On a good, coherant system, the second it's right you'll know it.

If you are using a tube preamp or an opamp based preamp (which includes most receivers and integrateds made since the late 80's) make sure you don't need to switch polarity of the speaker cables. If they are shielded cables, switch them at the speaker not the amp in case the shield is connected to the black so as to earth the shield.

can't expect much else.