Sound issue with Kenwood turntable

I have a Kenwood KP-2022A turntable, which has been mentioned on the forum before when I was looking for a cartridge and counterweight. Since purchasing the cartridge, stylus, and generic counterweght from John111, I have not been using it too often. Recently, it has developed a problem in the right channel. There is a constant hum coming from that channel, and when I play a record, the music is only heard through the left channel. If anybody can assist, I would really appreciate it.