So, first off, I'm pretty new to this, but enjoying amp building so far.

I have done a few CBG amps using the CB Gitty amp kit, and that has gone fine. My latest thing was to use that kit, but with two speakers instead of the one. I pulled the speakers out of a set of PC speakers that are 6 ohm and 2.5 watt and wired them parallel, stuck it all in the cigar box, and tested it. It was fine for awhile, but soon enough started squealing, even with nothing plugged into it. And the tone of this squeal could be affected by moving the wires or components. The only thing I have tried to fix it was to wire the speakers in a series, but this did not help. Any ideas about what could be doing this? Problems with using a differently rated speaker? The one with the CB Gitty kit is rated as 1 watt, 8 ohm. Bad connections? Like I said, I am super new to this, so anything would help.