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The ones you ordered will probably work fine, but Ebay vendors can be a gamble.
The TDA2822M in the 8 pin DIP has been discontinued by the original manufacturer
? ?
It was a popular device, and perhaps a dozen different shops are now building clones of it.
The original device was spec'd for operation to 12v, an "absolute max" of 15v beyond which it might be destroyed.
Some clones lowered the "absolute max" on their datasheet to 12v.
And some of those clones, even if they have a datasheet claiming 12v max, would be destroyed if used beyond 8v or so.
Most clones don't have a datasheet.

If I were to buy a replacement part, I'd go with the JRC?NJM2073D as recommended by Raj,
and buy it from a reputable distributor who I know will not be substituting some clone.
Some Ebay sellers go so far as to scrape off the markings of a cheaper low frequency TO220 FET, mark it as a $0.50 IRF510.

Regarding the stock v3 uBitx, they all apparently went out with either FCI or WX branded TDA2822M's.
Very few of the FCI brand parts had troubles, though you could exceed power dissipation limits
if operating at 12v or more, with volume up to full blast, and/or driving into less than 8 ohms.
Some WX brand parts worked fine at 12v, others blew in a puff of smoke at some random moment.
When buying replacement TDA2822M's on the web, there are many other clones beyond FCI and WX that you might get,
some of them have similar issues to the WX, few have a datasheet, almost none claim an absolute max of 15v.

I am not aware of problems with any of the LM386 clones blowing at supply voltages of 12v,
though some have far more distortion than others
? ?
.
Possible fixes for those with the WX brand TDA2822M parts in their v3 uBitx:
? ? Replace with a?NJM2073D or similar known good clone
Hack in an LM386 following the schematic of the v5 or v6 uBitx, a matter of swapping pins around on that DIP-8 part..
? ? Use one of the many LM386 amplifier breakout boards available on the web, tie it into the volume pot wiper.
? ? Reduce the supply voltage into the WX TDA2822M to 6v (instead of the stock 12v) by adding a 3 terminal voltage regulator?
? ? Adding an 8 ohm resistor in series with the output of the TDA2822M is not a bad idea, but the primary issue is the supply voltage.

The TDA2822 was a fine choice for the v3, I was sad to see it dropped on the v4.
The issue was simply one of buying sub-standard parts.?
That can happen with most any electronic part if you are pressing for low cost.

Another v3 issue regarding substandard parts was the provided BNC connector,
some of them were machined out of spec such that the center pin did not make good contact.
The antenna connection was intermittent when the coax was wiggled, subjecting the finals to high SWR..
That does not mean BNC connectors should be avoided, it means you must choose a vendor that sells good parts.

A search for "TDA2822" in this forum will find some very long discussions about all of this when the uBitx came out.
There were a half dozen different theories as to why some failed, it took months to figure out that it was primarily
a problem of the WX brand parts failing when powered from more than around 8v.

Jerry, KE7ER