HP50g : Symbolic solver oddities or user errors?

[Vtile]

Ok, well I pulled my notes out, it were even more simplistic I did remember. The first problem I encountered with the HP50g CAS were a equation: 1389=1.5*500*X^0.6 where 1.5 is a variable, but this time given as a number. So nothing too complex.
Solution would be something like X=(1380/(1.5*500))^(10/6)

So I did want a "non aproximated" answer for later use so I turned the approx mode off also the flag 123 - Forb. Swirch Mode is true in setting behing MODE key to not allow aproximation turned on while using solve. Now..

I prefer the equation editor for entering these so keystrokes would be:
1390 r.shift = 1 . 5 * 500 * X y^x 0 . 6 ENTER (to enter the equation to stack and exit from EQW.
In stack view:
X ENTER L.shift S.SLV 6 OK (no soft menu enabled atm. so it is pop-up menu)
"Solve ERROR: Non unary operator" <- Seriously wtf???

If aprox mode is on the answer would be e^(1.67*LN(1.852)) <- non interested about

... Now this is getting interesting, I can not replicate above anymore. The flag 123 seems not to stay up and the SOLVE command asks every time if I want to turn aprox mode ON yes/no, if no it just gives "SOLVE Error: Mode switch cancelled" .. Pulling my hair off atm...

Resetting with F1+F6+ON doesn't allow me to answer NO to question "Try to Recover Memory" what the hell is going on with this pile of silicon chips.

How I can make a full force reset that resets all and everything to factory defaults, microwave oven??

..I'm so sos os so .......

PS. Heh. Command VER gives information:
"HP49 CAS by Parisse, Heiskanen & Fiechter
4.20060919"
I though I purchased 50g not 49 .. Is the CAS version up to date or are this Chinese pirate copy (wouldn't not be too suprised if such would exist) it also number "HPK-49GPLUS(B)" at the back oh the calc while above the display it says what it should 50g..

PPS. Seriously, this unit have made some odd thing along this year I have had it. At times it do not take key presses at once and then when pressing again it doubles the press, once the keyboard test behind "F1+F6+On" menu the keyboard didn't take Up-arrow, but after reboot anything were fine again, now this thing with CAS. Unfortunately HPs are rare like hen's teeth here these days (assuming it is because of super restrictive and conservative high school exam rules and TI&Casio are stronger at that stage what to offer and later just phone/laptop) so I can not have other unit just to check if mine is foulty. :/