Help needed with calibration error

[BAinAK]

After many hundreds of flights with my old workhorse Solo, suddenly today it got a bit wobbly while airborne, then auto-landed (safely, thank goodness). Upon re-try the controller kept showing "calibration error - restart Solo" message. Brought it back the shop and went through both compass and level calibration. Compass indicated successful calibration, but level keeps showing 'calibration failed - try again.' Tried several more times (from a level concrete pad). I have now powered down and rebooted the entire system 5 or 6 times, but just when it looks like it's all ready to fly, the error message shuts it down again. Any ideas, my friends and Solo hold-outs?
P.S. I knew Solo's days are limited, but it has been working great until this.

 

[Saijin_Naib]

Looks like your Solo might be a candidate for the "belly slap" method.

Search here for various posts involving that, or simply (powered off/props off, etc), turn it upside down, supporting it firmly in one hand, and firmly rap the belly of the Solo with your open palm.

Your problems sound symptomatic of a sticky IMU, and this has been noted to cure this many times.

Or, new Cube time

 

[BAinAK]

Looks like your Solo might be a candidate for the "belly slap" method.

Search here for various posts involving that, or simply (powered off/props off, etc), turn it upside down, supporting it firmly in one hand, and firmly rap the belly of the Solo with your open palm.

Your problems sound symptomatic of a sticky IMU, and this has been noted to cure this many times.

Or, new Cube time

Saijin, you saved the day! that fixed it. Thank you!
You're a fan of the Cube?

 

[Saijin_Naib]

Saijin, you saved the day! that fixed it. Thank you!
You're a fan of the Cube?

Just repeating advice I've seen many other give in the same situation. Glad it worked for you!

On paper and in theory, I'm a big fan of the Green Cube. However, I've not made the jump myself yet due to tight margins on my hobby budget, especially since I'd like to go HERE2+Cube in one fell swoop, which puts me at the same expenditure as a NIB Bebop2 FPV Pack.