Crate bt220 bass amp, turns on, built in tuner is sensing the pitch but no sound is coming out

SOURCE: Crate bass amp bt220 limit led is flashing

You can reach the limiting IRRESPECTIVE of where the volume control is set when you have a guitar or other source that has HIGH output.

Guitars that have battery in them with internal amplifiers are an example of a high output guitar. Plain inductive pickups may require the volume control to be set at say 70% to reach limiting.

Please NOTE that the volume control is NOT linear, but is an "audio taper".

Limiting means you are probably driving it too hard. Many learn the hard way when speakers and thee power amp fail.

When the cone is driven too far beyond the pole pieces of the magnet, then the IMPEDANCE of the speaker becomes relatively low and can damage the power amp. The limiter tries to prevent this by sensing the current and or voltage and will back off the gain internally. This causes distortion when it happens.

SOURCE: Crate Bass Amp B100 - No sound.

Do you happen to have another speaker that you could hook up to speaker output? This would bypass the amps internal speaker and lf you get sound from that setup, it would mean either a jack failure or possible internal speaker problems. Please let me know.