I've bought a second hand warwick blue cab 15 today because i wanted a practice amp, headphone socket and kick back design is good. The problem i getting is the bass combo is distorting no matter what bass i play (both active and passive). All EQ is flat and it still distort ........ making it difficult to play. So out of interest i plug in a acoustic guitar and it sounded fine even with high volume and crack the bass EQ as well. It seems it only produce the distortion on bass guitar ........ Speaker problem or bass is too hot for this little amp?