MAMEWorld Forums - The Loony Bin - question about speakers & amps

I'm a novice when it comes to speaker systems, so hopefully someone can help me out. Here is what I'm working with (spec information is based on what I've found on the internet):

Peavey PV 1500 Stereo Power Amp
circa 2005
750W/ch @ 2 ohms
500W/ch @ 4 ohms
300W/ch @ 8 ohms
Input Gain Knobs set to max (+32 dB) for both inputs
DDT enabled for both inputs
High-Pass/Low-Cut 40 Hz filter enabled for both inputs
Channel A (Left) Speakon connector -> 1 speaker
Channel B (Right) Speakon connector -> 1 speaker

Peavey Model-115 International Series III Oak Speakers
circa 1989
3-way: 1505-8 Black Widow woofer, 22XT driver w/ CH-3R horn, HT-94 tweeter
8 ohms
200W continuous / 400W program / 800W peak
Crossover 1500 Hz & 8000 Hz

The right speaker (B) sounds fine, but the left speaker (A) is barely playing any sound. The DDT light for channel A flashes red from time to time. The fan on the power amp seems to run faster at random times, even if there isn't a lot of loud sound being played.

I'm trying to figure out if the speakers are considered connected in parallel, which from what I've read would mean that the amp is running 4 ohms instead of 8 ohms. If that's true, it would mean that the 400W speakers are getting 500W, which could be the reason that the left one isn't working properly now.

Here is my proposed solution: hook the good speaker to the channel A output and have the channel B output empty, while also turning down the channel B gain knob to the min setting. The amp would then send 300W to the 400W speaker and the fan shouldn't be running in fast mode since it's not under stress.

Does that seem right and is there any way I could get the bad speaker working again?

Thanks.