Basscube 15 hums only in "Auto" mode?

ARE YOU PARKED KEY OR KEY ON RUNNING.
SEE QUOTE PAGE32.
READ THE USERS GUIDE FREE IN THE GLOVE BOX
MINE 2010, DAY 1, I SET ALL LAMPS INSIDE TO DISABLED
THAT WAY NEVER COME BACK TO CAR WITH DEAD BATTERY NOW FOR 12 YEARS NOW, BY MY ACTS.
BUT MANUALS SWITCHES DO WORK.
This gets tricky with 3 switches in the car ,mine , 2 dome
and one on the head lamp lever.
even opening doors on mine, no dome lamp, by may settings, in the manual.
car run perfectly day or night ,correct?
one can say manual 2ways.]
at lever /button on dome.
or open any door is a manual act,
I disable every one allowed, by my needs. cover how in the guide
NO LED upgrades correct.?
mine the dome switches are on, off , auto, so I use off, and they never come on. ever.
on yours it is different PAGE 32 USERS GUIDE QUOTES,
"To protect the battery, the interior lights will
turn off automatically 15 minutes after the
ignition is moved to the LOCK position.
THIS SAVES BATTERY IF THEY FAIL.(MY COMMENT)
"This
will occur if the interior lights were switched
on manually or are on because a door is open.
This includes the glove compartment light
and the cargo area light.
To restore interior
light operation, either place the ignition in
the ON/RUN position or cycle the light
switch."

THIS IS A SUPER GOOD FEATURE,.
WRECKING $175 BATTERY IS NOT. CHEAP OR EVER FUN.

The headlamps may be turned on in 2 different ways. First, when the driver places the headlamp switch in the HEADLAMP position, normal operation occurs. Second, with the headlamp switch is placed in the AUTO position, automatic lamp control (ALC) occurs. During ALC control, the headlamps will be in daytime running lamp (DRL) operation in daylight conditions, or low beam operation in low light conditions. Headlamps
The headlamp driver module (HDM) is an electronic module that provides electrical power to the vehicle low beam headlamps. The HDM is controlled by a pulse width modulated (PWM) ground signal from the body control module (BCM). The BCM determines the desired lamp intensity using the ambient light sensor, multifunction switch and the park brake switch as inputs. In general, the HDM will operate in 1 of 3 modes:
• Reduced Intensity Mode: This mode is used by features that do not require or allow maximum low beam headlamp intensity such as daytime running lights (DRL) (nominal: 85% duty cycle).
• Full Intensity Mode: This mode is used by features that require full low beam headlamp intensity such as low beam headlamp operation in manual or auto modes (nominal: 100% duty cycle).
• Off Mode: This is the default mode of the system that will occur when none of the features described above are active. The BCM will deactivate its PWM output (0% duty cycle) during this mode.

The HDM - is just a relay in the under hood fuse box . That is probably your problem . HDM relay #46 , fuse's HDM fuse's #53 for 4.2 l engine or fuse # 57 for 5.3 l engine . both are 15 amp.

Found the problem with mine that had identical symptoms... after taking the lid off. i took the pressure switch off the hose. blew on the pressure switch when filling and you can hear the 3 clicks. the machine resumed onto next phase. i blew down the hose and this was clear and bubbling into machine. but then i discovered half way down the hose - it was damaged and had a hole. presumably from the drum rubbing on the hose over many years. now just need too replace this and it should work fine.

when doing the diagnostic testing machine fill up almost full and stop display an ol mode

I have GM40 timer sitting in front of me.
I cannot understand your question because I do not know what the 'control shaft' is.
If you mean the black-colored FM1 clock dial with captive trippers, then this dial is supposed to rotate continually as long as timer has power.
http://waterheatertimer.org/images/FM-1-Grasslin-Intermatic-20.jpg

Grasslin/Intermatic GM40 page
http://www.intermatic.com/products/grasslin/electromechanical%20time%20switches/multi-voltage%20time%20switches.aspx
The manual says quote:
With the manual switch in the middle position, the GM40 is in automatic mode and will switch at the programmed times. In the upper position "I", the load is permanently ON. In the lower position, "O", the load is permanently OFF. End quote.
In any switch position, the FM1 clock dial will continually rotate.

If your Load does not turn on-and-off according to the trippers set on FM1 clock dial, then 1) wiring is suspect or 2) if dip switches are not correctly set before applying voltage, and timer could be damaged.

The timer arrives with dip switches pre-set for 277Volts.

You can also manually rotate clock dial clockwise to observe when the load turns on-off.

Add a comment and give more information.
I would like to know what the 'control shaft' is, and what voltage you are using, and what dips switch setting you have, and which wires are connected to each terminal.

check your airflow. grills open, filter clean etc. typically when a unit runs once and won't come back on without a reset it points to a safety switch that is kicking the unit out. By cycling power you are resetting the switch until the next trip. Many times related to lack of airflow.

If you need further help, reach me via phone at https://www.6ya.com/expert/thomas_092728000e6acb79

You may have a power problem. Check to make sure that your wires aren't touching and not crossed.If this doesn't help try plugging in you sub to different plug could be getting interference electrically in the spot it's in

My auto function on my GE outdoor timer didn't work orginally. So, I programmed the "on" time to be 5 minutes from the current time (10:15 p.m.), and the "off" time to be the time I wanted (10:30 p.m.). Then I put it on automatic and waited for 10:15 p.m. to arrive. It turned on. Then, I set the "on" time to 5:30 p.m. and it works fine now. Apparently, it has to cycle through the "on" time in order to activate the auto function.

Edwards Electronics on ebay repairs these amps - contact them for pricing ;)

this may be result of blown capacitor - have it analyzed by applying strong magnet over the inside speaker , if humming persists, then its not blown capacitor -- the capacitor stores energy, and if that energy is lossed an out in the airwaves, thats the humming effect